[gnome-software/gnome-3-34] trivial: Move the CI to F31 to avoid a large download for each pull request

[Richard Hughes <rhughes src gnome org>]

commit 63d55f0d75f0a6bc91418074782131a1be34f337
Author: Richard Hughes <richard hughsie com>
Date:   Wed Nov 6 15:24:47 2019 +0000

    trivial: Move the CI to F31 to avoid a large download for each pull request

 .gitlab-ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index ffc358b3..37d7008f 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,4 +1,4 @@
-image: fedora:30
+image: fedora:31
 
 stages:
   - build