Add CI job for fixture regeneration

.github/workflows/fixtures.yml

@@ -0,0 +1,49 @@
+name: Trigger Fixture Regeneration
+
+on:
+  pull_request:
+    types:
+      - labeled
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  trigger_pipeline:
+    if: github.event.label.name == 'regenerate-fixtures'
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          token: ${{ secrets.RYAN_FIXTURE_GEN_PAT }}
+
+      - name: Set up Go
+        uses: actions/setup-go@v1
+        with:
+          go-version: 1.22.x
+
+      - uses: actions-ecosystem/action-create-comment@v1
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          body: |
+            Triggered a [Github Actions](${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}) job to update fixtures.
+
+      - uses: actions-ecosystem/action-remove-labels@v1
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          labels: regenerate-fixtures
+
+      - name: Regenerate Fixtures
+        run: CODECRAFTERS_RECORD_FIXTURES=true make test 
+
+      - name: Update Fixtures
+        run: |
+          git config --global user.email "[email protected]"
+          git config --global user.name "Ryan Gang"
+          git remote set-url origin https://ryan-gang:${{ secrets.RYAN_FIXTURE_GEN_PAT }}@github.com/codecrafters-io/shell-tester.git
+          git fetch origin ${{ github.head_ref }}
+          git checkout ${{ github.head_ref }}
+          git diff --quiet || (git add . && git commit -m "ci: add regenerated fixtures" && git push)