easy-builder: the immediate build retry does not fix the random linking issue on...

easy-builder: the immediate build retry does not fix the random linking issue on macOS that usually desappear on rebuilding

Unfortunately retrying immediately does not help, while doing it by hand some time later does, I have no proper explanation yet:

```
[100%] Linking CXX executable ../netradiant
Undefined symbols for architecture x86_64:
  "_gdk_gl_config_new", referenced from:
      glconfig_new() in libgtkutil.a(glwidget.cpp.o)
      glconfig_new_with_depth() in libgtkutil.a(glwidget.cpp.o)
  "_gdk_gl_config_new_by_mode", referenced from:
      glconfig_new() in libgtkutil.a(glwidget.cpp.o)
      glconfig_new_with_depth() in libgtkutil.a(glwidget.cpp.o)
  "_gdk_gl_drawable_get_type", referenced from:
      _glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_make_current(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
      glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_swap_buffers(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
  "_gdk_gl_drawable_gl_begin", referenced from:
      _glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_make_current(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
      glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
  "_gdk_gl_drawable_swap_buffers", referenced from:
      glwidget_swap_buffers(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
  "_gtk_widget_get_gl_context", referenced from:
      _glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_make_current(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
      glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_enable_gl(ui::GLArea, ui::Widget, void*) in libgtkutil.a(glwidget.cpp.o)
  "_gtk_widget_get_gl_window", referenced from:
      _glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_make_current(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
      glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_swap_buffers(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
  "_gtk_widget_is_gl_capable", referenced from:
      glwidget_enable_gl(ui::GLArea, ui::Widget, void*) in libgtkutil.a(glwidget.cpp.o)
  "_gtk_widget_set_gl_capability", referenced from:
      glwidget_enable_gl(ui::GLArea, ui::Widget, void*) in libgtkutil.a(glwidget.cpp.o)
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [netradiant] Error 1
make[1]: *** [radiant/CMakeFiles/netradiant.dir/all] Error 2
make: *** [all] Error 2
+ task_build
+ make -j8
[  0%] Built target cm
[  0%] Built target filematch
[  1%] Built target archivepak
[  3%] Built target mathlib
[  3%] Built target fastlz
[  3%] Built target l_net
[  6%] Built target recast
[  8%] Built target detour
[  9%] Built target ddslib
[  9%] Built target archivewad
[  9%] Built target archivezip
[ 10%] Built target etclib
[ 10%] Built target imagehl
[ 10%] Built target imagepng
[ 11%] Built target imageq2
[ 12%] Built target imagewebp
[ 12%] Built target xmllib
[ 14%] Built target entity
[ 15%] Built target mapq3
[ 15%] Built target iqmmodel
[ 18%] Built target md3model
[ 18%] Built target shaders
[ 19%] Built target container
[ 19%] Built target cmdlib
[ 20%] Built target debugging
[ 24%] Built target generic
[ 25%] Built target picomodel
[ 25%] Built target uilib
[ 25%] Built target math
[ 25%] Built target memory
[ 25%] Built target os
[ 25%] Built target modulesystem
[ 26%] Built target profile
[ 26%] Built target script
[ 26%] Built target signal
[ 26%] Built target stream
[ 27%] Built target string
[ 29%] Built target includes
[ 30%] Built target splines
[ 30%] Built target libs
[ 37%] Built target qdata3
[ 39%] Built target image
[ 40%] Built target crnrgba
[ 41%] Built target vfspk3
[ 50%] Built target q3data
[ 54%] Built target q2map
[ 55%] Built target daemonmap
[ 56%] Built target h2data
[ 58%] Built target model
[ 58%] Built target mapxml
[ 59%] Built target imagecrn
[ 59%] Built target modules
[ 72%] Built target gtkutil
[ 75%] Built target q3map2
[ 75%] Built target shaderplug
[ 75%] Built target sunplug
[ 76%] Built target prtview
[ 77%] Built target ufoaiplug
[ 78%] Built target brushexport
[ 83%] Built target bobtoolz
[ 84%] Linking CXX executable ../netradiant
Undefined symbols for architecture x86_64:
  "_gdk_gl_config_new", referenced from:
      glconfig_new() in libgtkutil.a(glwidget.cpp.o)
      glconfig_new_with_depth() in libgtkutil.a(glwidget.cpp.o)
  "_gdk_gl_config_new_by_mode", referenced from:
      glconfig_new() in libgtkutil.a(glwidget.cpp.o)
      glconfig_new_with_depth() in libgtkutil.a(glwidget.cpp.o)
  "_gdk_gl_drawable_get_type", referenced from:
      _glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_make_current(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
      glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_swap_buffers(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
  "_gdk_gl_drawable_gl_begin", referenced from:
      _glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_make_current(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
      glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
  "_gdk_gl_drawable_swap_buffers", referenced from:
      glwidget_swap_buffers(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
  "_gtk_widget_get_gl_context", referenced from:
      _glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_make_current(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
      glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_enable_gl(ui::GLArea, ui::Widget, void*) in libgtkutil.a(glwidget.cpp.o)
  "_gtk_widget_get_gl_window", referenced from:
      _glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_make_current(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
      glwidget_context_created(ui::GLArea, void*) in libgtkutil.a(glwidget.cpp.o)
      glwidget_swap_buffers(ui::GLArea) in libgtkutil.a(glwidget.cpp.o)
  "_gtk_widget_is_gl_capable", referenced from:
      glwidget_enable_gl(ui::GLArea, ui::Widget, void*) in libgtkutil.a(glwidget.cpp.o)
  "_gtk_widget_set_gl_capability", referenced from:
      glwidget_enable_gl(ui::GLArea, ui::Widget, void*) in libgtkutil.a(glwidget.cpp.o)
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [netradiant] Error 1
make[1]: *** [radiant/CMakeFiles/netradiant.dir/all] Error 2
make: *** [all] Error 2
```