Crowdin: experiment to fix crowdin 'ghost' strings
Crowdin: experiment to fix crowdin 'ghost' strings

The following translation strings still perpetuate after updating crowdin translations. This commit experiments with removing their source counterparts in the FC .ts files. I'm not sure why they are not rendered obsolete by the normal operations. 
  
* https://crowdin.com/translate/freecad/6766/en-en#6499472  
* https://crowdin.com/translate/freecad/6766/en-en#6573450
Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master