Remove duplicate text from exporter configuration dialog.

Checkboxes display the same text on both sides of the checkbox,
which looks bad. This patch clears the text from the checkbox so
that only the label on the left is displayed.

Change-Id: I1cb7418c528fd1025eb1e5f0052ab0186ab8765b
Merge topic '13846-CleanGL2PSExporterDialog' into next

c749f01 Remove duplicate text from exporter configuration dialog.