FindGmsh: install if the GmshIO plugin is enabled
Finding ParaView without components requires everything, so this needs to be provided so that the dependent target can be created when finding ParaView itself.
Fixes: #21361
Cc: @mirenradia
Finding ParaView without components requires everything, so this needs to be provided so that the dependent target can be created when finding ParaView itself.
Fixes: #21361
Cc: @mirenradia