(MAINT) Adding workflow restarter

.github/workflows/workflow-restarter-test.yml

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+name: Workflow Restarter TEST
+
+on:
+  workflow_dispatch:
+    inputs:
+      fail:
+        description: >
+          For (acceptance, unit) jobs: 
+          'true'  = (fail, succeed) and 
+          'false' = (succeed, fail)  
+        required: true
+        default: 'true'
+env:
+  SOURCE_GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+jobs:
+  unit:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Check outcome
+      run: |
+        if [ "${{ github.event.inputs.fail }}" = "true" ]; then
+          echo "'unit' job succeeded"
+          exit 0
+        else
+          echo "'unit' job failed"
+          exit 1
+        fi
+  acceptance:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Check outcome
+      run: |
+        if [ "${{ github.event.inputs.fail }}" = "true" ]; then
+          echo "'acceptance' job failed"
+          exit 1
+        else
+          echo "'acceptance' job succeeded"
+          exit 0
+        fi
+
+  on-failure-workflow-restarter-proxy:
+    # (1) run this job after the "acceptance" job and...
+    needs: [acceptance, unit]
+    # (2) continue ONLY IF "acceptance" fails
+    if: always() && needs.acceptance.result == 'failure' || needs.unit.result == 'failure'
+    runs-on: ubuntu-latest
+    steps:
+      # (3) checkout this repository in order to "see" the following custom action
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      # (4) "use" the custom action to retrigger the failed "acceptance job" above
+      # NOTE: pass the SOURCE_GITHUB_TOKEN to the custom action because (a) it must have
+      # this to trigger the reusable workflow that restarts the failed job; and
+      # (b) custom actions do not have access to the calling workflow's secrets
+      - name: Trigger reusable workflow
+        uses: "puppetlabs/cat-github-actions/.github/actions/workflow-restarter-proxy@main"
+        env:
+          SOURCE_GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          repository: ${{ github.repository }}
+          run_id: ${{ github.run_id }}

.github/workflows/workflow-restarter.yml

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+# target-repo/.github/workflows/call-reusable-workflow.yml
+name: Workflow Restarter
+on:
+  workflow_dispatch:
+    inputs:
+      repo:
+        description: "GitHub repository name."
+        required: true
+        type: string
+      run_id:
+        description: "The ID of the workflow run to rerun."
+        required: true
+        type: string
+      retries:
+        description: "The number of times to retry the workflow run."
+        required: false
+        type: string
+        default: "3"
+
+jobs:
+  call-reusable-workflow:
+    uses: "puppetlabs/cat-github-actions/.github/workflows/workflow-restarter.yml@main"
+    with:
+      repo: ${{ inputs.repo }}
+      run_id: ${{ inputs.run_id }}
+      retries: ${{ inputs.retries }}