no comma needed

Author: Mariatta

backport/backport_pr.py

@@ -38,7 +38,7 @@ async def backport_pr(event, gh, *args, **kwargs):
                 thanks_to = f"Thanks @{created_by} for the PR 🌮🎉."
             else:
                 thanks_to = f"Thanks @{created_by} for the PR, and @{merged_by} for merging it 🌮🎉."
-            message = f"{thanks_to}. I'm working now to backport this PR to: {', '.join(branches)}.",\
+            message = f"{thanks_to}. I'm working now to backport this PR to: {', '.join(branches)}."\
                       f"\n🐍🍒⛏🤖 {easter_egg}"
 
             util.comment_on_pr(issue_number, message)