Add T-compiler backports Zulip notifications

Author: apiraino

triagebot.toml

@@ -691,6 +691,41 @@ message_on_remove = "Issue #{number}'s nomination has been removed. Thanks all f
 message_on_close = "Issue #{number} has been closed. Thanks for participating!"
 message_on_reopen = "Issue #{number} has been reopened. Pinging @*T-types*."
 
+[notify-zulip."beta-nominated".compiler]
+required_labels = ["T-compiler"]
+zulip_stream = 474880 # #t-compiler/backports
+topic = "#{number}: beta-nominated"
+message_on_add = [
+    """\
+@**channel** PR #{number} "{title}" has been nominated for beta backport.
+""",
+    """\
+/poll Approve beta backport of #{number}?
+approve
+decline
+don't know
+""",
+]
+message_on_remove = "PR #{number}'s beta-nomination has been removed."
+
+[notify-zulip."stable-nominated".compiler]
+required_labels = ["T-compiler"]
+zulip_stream = 474880 # #t-compiler/backports
+topic = "#{number}: stable-nominated"
+message_on_add = [
+    """\
+@**channel** PR #{number} "{title}" has been nominated for beta backport.
+""",
+    """\
+/poll Approve beta backport of #{number}?
+approve
+approve (but does not justify new dot release on its own)
+decline
+don't know
+""",
+]
+message_on_remove = "PR #{number}'s stable-nomination has been removed."
+
 [notify-zulip."A-edition-2021"]
 required_labels = ["C-bug"]
 zulip_stream = 268952 # #edition