fix: skip check if changes array is empty

jenkins/webhook-proxy/main.go

@@ -395,8 +395,10 @@ func (s *Server) HandleRoot() http.HandlerFunc {
 			// Skip requests with where the ref id is starting with "refs/notes/"
 			// Reference 1: https://community.atlassian.com/t5/Bitbucket-questions/disable-quot-git-notes-add-quot-behaviour-for-semantic-release/qaq-p/1837322
 			// Reference 2: https://github.com/semantic-release/semantic-release/discussions/2017#discussioncomment-995308
-			if strings.Contains(req.Changes[0].Ref.DisplayID, "refs/notes/") {
+			if len(req.Changes) > 0 && strings.Contains(req.Changes[0].Ref.DisplayID, "refs/notes/") {
 				log.Println(requestID, "Skipping request with refs/notes/ prefix in ref id")
+				// Return 200 OK to Bitbucket to avoid retries
+				http.Error(w, "OK", http.StatusOK)
 				return
 			}