[vala/wip/ci] Use Fedora 29 -- https://bugzilla.redhat.com/show_bug.cgi?id=1668843

[Rico Tzschichholz <ricotz src gnome org>]

commit 7c19e9f38f7e625f9bb78dd41c2bc04d335ac447
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Sun Feb 10 13:42:44 2019 +0100

    Use Fedora 29 -- https://bugzilla.redhat.com/show_bug.cgi?id=1668843

 .gitlab-ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 13bd5f1ed..bca9a14cd 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -4,7 +4,7 @@ stages:
 
 fedora-gcc-x86_64:
   stage: build
-  image: fedora:rawhide
+  image: fedora:29
   except:
     - tags
   before_script: