ci: add pull request triage and Kodiak merge workflow (#9109)

* chore: enable kodiak for auto merges

* ci: add pull request triage

* ci: update kentaro-m/auto-assign-action

This supports Node.js 16.

---------

Co-authored-by: iCrawl <buechler.noel@outlook.com>

.github/labeler.yml

@@ -0,0 +1,15 @@
+apps:guide:
+  - apps/guide/*
+  - apps/guide/**/*
+apps:website:
+  - apps/website/*
+  - apps/website/**/*
+packages:discord.js:
+  - scripts/*
+  - scripts/**/*
+  - src/*
+  - src/**/*
+  - test/*
+  - test/**/*
+  - typings/*
+  - typings/**/*