[v10.0.x] Chore: Add auto-milestone workflow for pull-requests (#71706)

Chore: Add auto-milestone workflow for pull-requests (#71177)

This adds a new auto-milestone workflow that will set the milestone for
a PR when it is closed. This way, contributors no longer have to think
about milestone at all.

(cherry picked from commit 8ae92db53d)

.github/CODEOWNERS

@@ -582,6 +582,7 @@ embed.go @grafana/grafana-as-code
 /.github/pr-commands.json @marefr
 /.github/renovate.json5 @grafana/frontend-ops
 /.github/teams.yml @armandgrillet
+/.github/workflows/auto-milestone.yml @grafana/grafana-delivery
 /.github/workflows/backport.yml @grafana/grafana-delivery
 /.github/workflows/bump-version.yml @grafana/grafana-delivery
 /.github/workflows/close-milestone.yml @grafana/grafana-delivery

.github/pr-checks.json

@@ -1,11 +1,4 @@
 [
-  {
-    "type": "check-milestone",
-    "title": "Milestone Check",
-    "targetUrl": "https://github.com/grafana/grafana/blob/main/contribute/merge-pull-request.md#assign-a-milestone",
-    "success": "Milestone set",
-    "failure": "Milestone not set"
-  },
   {
     "type": "check-label",
     "title": "Backport Check",
@@ -46,4 +39,4 @@
     },
     "targetUrl": "https://github.com/grafana/grafana/blob/main/contribute/merge-pull-request.md#include-in-changelog-and-release-notes"
   }
-]
+]

.github/workflows/auto-milestone.yml

@@ -0,0 +1,22 @@
+name: Auto-milestone
+on:
+  pull_request:
+    types:
+      - closed
+
+jobs:
+  main:
+    runs-on: ubuntu-latest
+    steps:
+      - name: "Generate token"
+        id: generate_token
+        uses: tibdex/github-app-token@b62528385c34dbc9f38e5f4225ac829252d1ea92
+        with:
+          app_id: ${{ secrets.GRAFANA_DELIVERY_BOT_APP_ID }}
+          private_key: ${{ secrets.GRAFANA_DELIVERY_BOT_APP_PEM }}
+
+      - name: Run auto-milestone
+        uses: grafana/grafana-github-actions-go/auto-milestone@main
+        with:
+          pr: ${{ github.event.pull_request.number }}
+          token: ${{ steps.generate_token.outputs.token }}