[pygobject] subprojects: Use GLib main branch

[Patrick Griffis <pgriffis src gnome org>]

commit 34a9124736af79e53e4dd0d3b1081278624720ce
Author: Philip Withnall <pwithnall endlessos org>
Date:   Mon Jun 7 14:51:07 2021 +0100

    subprojects: Use GLib main branch
    
    GLib upstream has renamed its `master` branch to `main`.
    
    See https://gitlab.gnome.org/GNOME/glib/-/issues/2348.
    
    Signed-off-by: Philip Withnall <pwithnall endlessos org>

 subprojects/glib.wrap | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/subprojects/glib.wrap b/subprojects/glib.wrap
index 87021ae4..b492f238 100644
--- a/subprojects/glib.wrap
+++ b/subprojects/glib.wrap
@@ -2,4 +2,4 @@
 directory=glib
 url=https://gitlab.gnome.org/GNOME/glib.git
 push-url=git gitlab gnome org:GNOME/glib.git
-revision=master
+revision=main