[INFRA] Make pages.yml reuse the documentation image used in build_and_test

Run the documentation job inside the prebuilt documentation image (apache-spark-github-action-image-docs-cache:master-static) that build_and_test.yml already uses, dropping the redundant inline setup of the Python docs dependencies, Ruby, and Pandoc now provided by the image.

Author: zhengruifeng

.github/workflows/pages.yml

@@ -37,47 +37,37 @@ jobs:
       pages: write
     environment:
       name: github-pages # https://github.com/actions/deploy-pages/issues/271
+    container:
+      image: ghcr.io/apache/spark/apache-spark-github-action-image-docs-cache:master-static
     env:
       SPARK_TESTING: 1 # Reduce some noise in the logs
       RELEASE_VERSION: 'In-Progress'
+      LC_ALL: C.UTF-8
+      LANG: C.UTF-8
     if: github.repository == 'apache/spark'
     steps:
       - name: Checkout Spark repository
         uses: actions/checkout@v6
         with:
           repository: apache/spark
           ref: 'master'
+      - name: Add GITHUB_WORKSPACE to git trust safe.directory
+        run: |
+          git config --global --add safe.directory ${GITHUB_WORKSPACE}
+      - name: Free up disk space
+        run: ./dev/free_disk_space_container
       - name: Install Java 17
         uses: actions/setup-java@v5
         with:
           distribution: zulu
           java-version: 17
-      - name: Install Python 3.11
-        uses: actions/setup-python@v6
-        with:
-          python-version: '3.11'
-          architecture: x64
-          cache: 'pip'
-      - name: Install Python dependencies
-        run: |
-         pip install 'sphinx==4.5.0' mkdocs 'pydata_sphinx_theme>=0.13' sphinx-copybutton nbsphinx numpydoc jinja2 markupsafe 'pyzmq<24.0.0' \
-            ipython ipython_genutils sphinx_plotly_directive 'numpy>=1.23.2' pyarrow 'pandas==2.3.3' 'plotly>=4.8' 'docutils<0.18.0' \
-            'flake8==3.9.0' 'mypy==1.8.0' 'pytest==7.1.3' 'pytest-mypy-plugins==1.9.3' 'ruff==0.14.8' \
-            'pandas-stubs==1.2.0.53' 'grpcio==1.76.0' 'grpcio-status==1.76.0' 'protobuf==6.33.5' 'grpc-stubs==1.24.11' 'googleapis-common-protos-stubs==2.2.0' \
-            'sphinxcontrib-applehelp==1.0.4' 'sphinxcontrib-devhelp==1.0.2' 'sphinxcontrib-htmlhelp==2.0.1' 'sphinxcontrib-qthelp==1.0.3' 'sphinxcontrib-serializinghtml==1.1.5'
-      - name: Install Ruby for documentation generation
-        uses: ruby/setup-ruby@4dc28cf14d77b0afa6832d9765ac422dbf0dfedd # v1
-        with:
-          ruby-version: '3.3'
-          bundler-cache: true
-      - name: Install Pandoc
-        run: |
-          sudo apt-get update -y
-          sudo apt-get install pandoc
       - name: Install dependencies for documentation generation
         run: |
+          # Keep the version of Bundler here in sync with the following locations:
+          #   - dev/create-release/spark-rm/Dockerfile
+          #   - docs/README.md
+          gem install bundler -v 2.4.22
           cd docs
-          gem install bundler -v 2.4.22 -n /usr/local/bin
           bundle install --retry=100
       - name: Run documentation build
         run: |