[gnome-control-center] ci: Don't build when running the weekly image

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

commit cfca1426955e862635048875c56bfd8083db0765
Author: Georges Basile Stavracas Neto <georges stavracas gmail com>
Date:   Sun Nov 18 22:10:43 2018 -0200

    ci: Don't build when running the weekly image

 .gitlab-ci.yml | 8 ++++++++
 1 file changed, 8 insertions(+)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 5dabe4b86..ef642656c 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -58,6 +58,10 @@ build:
     # Save all but git-related files
     - rm -rf .git .gitignore .gitmodules
 
+  except:
+    variables:
+      - $CI_PIPELINE_SOURCE == "scheduled"
+
 ##
 # Stage: Test
 #
@@ -86,6 +90,7 @@ test:
 
   except:
     variables:
+      - $CI_PIPELINE_SOURCE == "scheduled"
       - $CI_COMMIT_TITLE =~ /^Update.*translation$/
 
 # Runs the coverage test.
@@ -112,6 +117,7 @@ coverage:
 
   except:
     variables:
+      - $CI_PIPELINE_SOURCE == "scheduled"
       - $CI_COMMIT_TITLE =~ /^Update.*translation$/
 
 # Runs the address sanitizer.
@@ -239,6 +245,7 @@ stop_review:
 
   except:
     variables:
+      - $CI_PIPELINE_SOURCE == "scheduled"
       - $CI_COMMIT_TITLE =~ /^Update.*translation$/
 
 asan:
@@ -289,6 +296,7 @@ msan:
 
   except:
     variables:
+      - $CI_PIPELINE_SOURCE == "scheduled"
       - $CI_COMMIT_TITLE =~ /^Update.*translation$/
 
 armv8: