ci: use primer integration app for status checks (#7158)

Author: joshblack

.github/workflows/status-checks.yml

@@ -13,6 +13,13 @@ jobs:
     runs-on: ubuntu-latest
     if: "${{ contains(github.event.pull_request.labels.*.name, 'integration-tests: skipped manually') }}"
     steps:
+      - name: Generate token for primer
+        id: generate_primer_token
+        uses: actions/create-github-app-token@67018539274d69449ef7c02e8e71183d1719ab42 # v2.1.4
+        with:
+          app-id: 902635
+          owner: 'primer'
+          private-key: ${{ secrets.PRIMER_INTEGRATION_APP_PRIVATE_KEY }}
       - name: Override status checks
         run: |
           # Get the timeline event ID for the label being added
@@ -39,6 +46,6 @@ jobs:
             -f description='Skipped' \
             -f target_url="$TARGET_URL"
         env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          GH_TOKEN: ${{ steps.generate_primer_token.outputs.token }}
           SHA: ${{ github.event.pull_request.head.sha }}
           PR_NUMBER: ${{ github.event.pull_request.number }}