Update dependency on GLib 2.30
Update dependency on GLib 2.30

GLib 2.30 is necessary for g_unix_open_pipe().

https://bugs.freedesktop.org/show_bug.cgi?id=47054

freedesktop-unofficial-mirror/telepathy__telepathy-mission-control,freedesktop-unofficial-mirror/telepathy__telepathy-mission-control,freedesktop-unofficial-mirror/telepathy__telepathy-mission-control,freedesktop-unofficial-mirror/telepathy__telepathy-mission-control