[stable-2.9] Limit Shippable matrix check to ansible repo.

(cherry picked from commit ada02f1966)

Co-authored-by: Matt Clay <matt@mystile.com>

test/utils/shippable/check_matrix.py

@@ -25,6 +25,13 @@ except ImportError:
 
 def main():  # type: () -> None
     """Main entry point."""
+    repo_full_name = os.environ['REPO_FULL_NAME']
+    required_repo_full_name = 'ansible/ansible'
+
+    if repo_full_name != required_repo_full_name:
+        sys.stderr.write('Skipping matrix check on repo "%s" which is not "%s".\n' % (repo_full_name, required_repo_full_name))
+        return
+
     with open('shippable.yml', 'rb') as yaml_file:
         yaml = yaml_file.read().decode('utf-8').splitlines()