Improve update_owners.py username detection and error message.

hack/update_owners.py

@@ -116,12 +116,12 @@ def get_maintainers():
 
 
 def detect_github_username():
-    remotes = subprocess.check_output(['git', 'remote', '-v'])
-    repos = set(re.findall(r'\w+(?=/kubernetes)', remotes))
-    repos.remove('kubernetes')
-    if len(repos) == 1:
-        return repos.pop()
-    raise ValueError('unable to guess GitHub user from `git remote -v` output, use --user instead')
+    origin_url = subprocess.check_output(['git', 'config', 'remote.origin.url'])
+    m = re.search(r'github.com[:/](.*)/', origin_url)
+    if m and m.group(1) != 'kubernetes':
+        return m.group(1)
+    raise ValueError('unable to determine GitHub user from '
+                     '`git config remote.origin.url` output, run with --user instead')
 
 
 def main():

test/list/main.go

@@ -237,7 +237,8 @@ func (t *testList) handlePath(path string, info os.FileInfo, err error) error {
 		return err
 	}
 	if strings.Contains(path, "third_party") ||
-		strings.Contains(path, "staging") {
+		strings.Contains(path, "staging") ||
+		strings.Contains(path, "_output") {
 		return filepath.SkipDir
 	}
 	if strings.HasSuffix(path, ".go") && strings.Contains(path, "e2e") ||