[gdk-pixbuf] Update glib.wrap

[Emmanuele Bassi <ebassi src gnome org>]

commit dc9c2d7990d53e97ebc888033a38c2f8ac753873
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Mon Jun 7 15:05:29 2021 +0100

    Update glib.wrap
    
    The default branch in GLib has been renamed to `main`.
    
    See: GNOME/glib#2348

 subprojects/glib.wrap | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/subprojects/glib.wrap b/subprojects/glib.wrap
index 0f72dc280..9e8b843fb 100644
--- a/subprojects/glib.wrap
+++ b/subprojects/glib.wrap
@@ -2,5 +2,5 @@
 directory=glib
 url=https://gitlab.gnome.org/GNOME/glib.git
 push-url=git gitlab gnome org:GNOME/glib.git
-revision=master
+revision=main
 depth=1