community/gnome-browser-connector: new aport, replaces chrome-gnome-shell

The main connector was split into a separate repository and the build system was changed to meson, so it made sense to re-make the package from scratch.

cc @team/gnome; who should I list as maintainer, given that this is one of the packages listed in #13931 (closed)? (It could probably be moved to the main GNOME app portion of the list since as far as I'm aware the only usage is for installing GNOME Shell extensions.)