Check style in documentation PRs

.github/workflows/docs_check.yml

@@ -92,6 +92,38 @@ jobs:
         with:
           name: changed_images
           path: ${{ runner.temp }}/changed_images.json
+  StyleCheck:
+    needs: DockerHubPush
+    runs-on: [self-hosted, style-checker]
+    if: ${{ success() || failure() }}
+    steps:
+      - name: Set envs
+        run: |
+          cat >> "$GITHUB_ENV" << 'EOF'
+          TEMP_PATH=${{ runner.temp }}/style_check
+          EOF
+      - name: Download changed images
+        # even if artifact does not exist, e.g. on `do not test` label or failed Docker job
+        continue-on-error: true
+        uses: actions/download-artifact@v2
+        with:
+          name: changed_images
+          path: ${{ env.TEMP_PATH }}
+      - name: Clear repository
+        run: |
+          sudo rm -fr "$GITHUB_WORKSPACE" && mkdir "$GITHUB_WORKSPACE"
+      - name: Check out repository code
+        uses: actions/checkout@v2
+      - name: Style Check
+        run: |
+          cd "$GITHUB_WORKSPACE/tests/ci"
+          python3 style_check.py
+      - name: Cleanup
+        if: always()
+        run: |
+          docker kill "$(docker ps -q)" ||:
+          docker rm -f "$(docker ps -a -q)" ||:
+          sudo rm -fr "$TEMP_PATH"
   DocsCheck:
     needs: DockerHubPush
     runs-on: [self-hosted, func-tester-aarch64]