Merge "github: prevent getRepoPermission to raise AttributeError" into feature/zuulv3

zuul/driver/github/githubconnection.py

@@ -824,6 +824,9 @@ class GithubConnection(BaseConnection):
         # Create a repo object
         repository = github.repository(owner, proj)
 
+        if not repository:
+            return 'none'
+
         # Build up a URL
         url = repository._build_url('collaborators', login, 'permission',
                                     base_url=repository._api)