Switch to posthog-bot PAT

Author: Piccirello

.github/workflows/release-please.yml

@@ -15,5 +15,5 @@ jobs:
     steps:
       - uses: googleapis/release-please-action@v4
         with:
-          token: ${{ secrets.RELEASE_PLEASE_PAT }}
-          release-type: node
+          token: ${{ secrets.POSTHOG_BOT_PAT }}
+          release-type: node