DT-581 Fix .deb search (core20)
requested to merge sergio-costas/gnome-software:DT-581_use_new_and_old_deb_repo_folders_core20 into snap-store-41
There was a change in the folders used by appstream to store the .deb repositories. Some systems still updates the old one, but others only update the new one.
This MR applies patch GNOME/gnome-software!1235 (merged) from Gnome Software, which should fix this, and thus ensuring that all the users get both .deb and .snap in their searchs.
Edited by Sergio Costas