Bundled GLib shadowed the system libraries for host plugins dlopen'd
into the process, like PipeWire's videoconvert on 1.6+, which would
break Wayland screen sharing on newer distros. This PR makes Zed rely on
system GLib instead, since the bundled version pulls from whatever is in
CI (presently Ubuntu 20.04).

Release Notes:

- Removed GLib libraries from Linux release bundle, which could conflict
with system plugins