gplugin/gplugin

Update the packaging and convey files for the gtk4 change

2021-10-04, Gary Kramlich
27b0c5e40a4b
Update the packaging and convey files for the gtk4 change

Testing Done:
Ran the fedora and debian packaging.

Reviewed at https://reviews.imfreedom.org/r/993/
EionRobb <> EionRobb <eion@robbmob.com>
ivanhoe <107501-ivanhoe@users.noreply.gitlab.com> ivanhoe <ivanhoe@fiscari.de>
Richard Laager <rlaager@pidgin.im> <rlaager@wiktel.com>