[gnome-calendar] ci: Use a Rawhide image

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 845eed5ceaafeb4c80885968371d8799b1b9526b
Author: Georges Basile Stavracas Neto <georges stavracas gmail com>
Date:   Sat Jan 27 12:52:14 2018 -0200

    ci: Use a Rawhide image
    
    We depend on an unstable version of GWeather.

 .gitlab-ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 247914ac..53adc4a8 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,4 +1,4 @@
-image: fedora:27
+image: fedora:rawhide
 stages:
   - build