invalid-label-bot: Fix typo

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

.github/workflows/invalid-label-bot.yaml

@@ -18,7 +18,7 @@ jobs:
                 + " Many helpful people will not see your message here and you"
                 + " are unlikely to get a useful response."
                 + " Please close this ticket and follow the contact directions"
-                + " at:
+                + " at:"
                 + " https://www.klipper3d.org/Contact.html"
                 + "\n"
                 + "We use github to share the results of work done to"