gplugin/gplugin

Fix some leaks in GTK3 plugin viewer

2021-10-09, Elliott Sales de Andrade
3c0fd3c606db
Fix some leaks in GTK3 plugin viewer

Add missing free for `abi_version` and `summary`, and put frees at end of function.

Testing Done:
Compile only.

Reviewed at https://reviews.imfreedom.org/r/1009/
EionRobb <> EionRobb <eion@robbmob.com>
ivanhoe <107501-ivanhoe@users.noreply.gitlab.com> ivanhoe <ivanhoe@fiscari.de>
Richard Laager <rlaager@pidgin.im> <rlaager@wiktel.com>