Remove comments questioning API capabilities

The APP API does indeed work the way the code is written, so we can
remove the comment questioning it.

Change-Id: I8989f87ab4bc5980ef2e6b5d765c0f42656d246d
Signed-off-by: Jesse Keating <omgjlk@us.ibm.com>
diff --git a/zuul/driver/github/githubconnection.py b/zuul/driver/github/githubconnection.py
index 2191f95..0ce6ef5 100644
--- a/zuul/driver/github/githubconnection.py
+++ b/zuul/driver/github/githubconnection.py
@@ -727,10 +727,6 @@
         else:
             exclude_unprotected = tenant.exclude_unprotected_branches
 
-        # TODO(mordred) Does it work for Github Apps to get repository
-        # branches? If not, can we avoid doing this as an API for projects that
-        # aren't trying to exclude protected branches by doing a git command
-        # (gerrit driver does an upload pack over ssh)
         github = self.getGithubClient(project.name)
         try:
             owner, proj = project.name.split('/')