RichTextLabel: proper handling of internal key events
RichTextLabel: proper handling of internal key events

Fixes #36211

(cherry picked from commit ff030afc936554ee93f7995d9c745b800ec9a0d7)

ex/godot,ex/godot,ex/godot,ex/godot,ex/godot,ex/godot,ex/godot,ex/godot