Use shared workflow for keep alive (#164)

.github/workflows/keep-alive.yml

@@ -5,27 +5,11 @@ on:
     - cron: 0 0 1 * * # Once every month
   workflow_dispatch:
 
-env:
-  GIT_USERNAME: "Exercism Bot"
-  GIT_EMAIL: "66069679+exercism-bot@users.noreply.github.com"
-
 jobs:
   keep_alive:
-    runs-on: ubuntu-22.04
-
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11
-        with:
-          token: ${{ secrets.PAT_EMPTY_COMMITS }}
-          fetch-depth: 0
-
-      - name: Configure the git user
-        run: |
-          git config --global user.email "$GIT_EMAIL"
-          git config --global user.name "$GIT_USERNAME"
-
-      - name: Create and push an empty commit
-        run: |
-          git commit --allow-empty -m "Empty commit"
-          git push origin main
+    if: github.repository_owner == 'exercism' # Stops this job from running on forks
+    uses: exercism/github-actions/.github/workflows/keep-alive.yml@main
+    with:
+      repository: ${{ github.event.repository.name }}
+    secrets:
+      pat_empty_commits: ${{ secrets.PAT_EMPTY_COMMITS }}