CI: fix changelog repo null (#90960)

* give secrets when running changelog action

* i guess secrets don't have types

.github/workflows/changelog.yml

@@ -18,6 +18,12 @@ on:
         required: false
         default: false
         type: boolean
+    secrets:
+      GRAFANA_DELIVERY_BOT_APP_ID:
+        required: true
+      GRAFANA_DELIVERY_BOT_APP_PEM:
+        required: true
+
   workflow_dispatch:
     inputs:
       version:
@@ -47,6 +53,12 @@ jobs:
     permissions:
       contents: write
     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: "Checkout Grafana repo"
         uses: "actions/checkout@v4"
         with:
@@ -66,7 +78,7 @@ jobs:
         id: changelog
         uses: ./.github/workflows/actions/changelog
         with:
-          github_token: ${{ secrets.GITHUB_TOKEN }}
+          github_token: ${{ steps.generate_token.outputs.token }}
           target: v${{ inputs.version }}
           output_file: changelog_items.md
       - name: "Patch CHANGELOG.md"