GH Actions/test: remove unused steps for PHPCS 4.x

Testing against PHPCS 4.x-dev has not been possible for a while and development of that version looks to be stagnated anyway, so testing against it is not really relevant at this time.

This commit removes all references to testing against PHPCS 4.x from the workflow.

If/when testing against the next PHPCS major becomes relevant again, this can brought back and adjusted based on the reality at that time.

.github/workflows/test.yml

@@ -52,11 +52,6 @@ jobs:
           #- php_version: '8.0'
           #  cs_dependencies: 'highest'
 
-          # Test against the next major of PHPCS. Temporarily disabled due to upstream bugs.
-          #- php_version: '7.4'
-          #  cs_dependencies: 'highest'
-          #  phpcs_version: '4.0.x-dev'
-
     name: "Test${{ matrix.cs_dependencies == 'highest' && ' + Lint' || '' }}: PHP ${{ matrix.php_version }} - CS Deps ${{ matrix.cs_dependencies }}"
 
     continue-on-error: ${{ matrix.php == '8.3' }}
@@ -70,7 +65,7 @@ jobs:
       - name: Setup ini config
         id: set_ini
         run: |
-          if [[ "${{ matrix.cs_dependencies }}" != "highest" && "${{ matrix.phpcs_version }}" != "4.0.x-dev" ]]; then
+          if [[ "${{ matrix.cs_dependencies }}" != "highest" ]]; then
             echo 'PHP_INI=error_reporting=E_ALL & ~E_DEPRECATED, display_errors=On' >> $GITHUB_OUTPUT
           else
             echo 'PHP_INI=error_reporting=-1, display_errors=On' >> $GITHUB_OUTPUT
@@ -83,33 +78,13 @@ jobs:
           ini-values: ${{ steps.set_ini.outputs.PHP_INI }}
           coverage: none
           tools: cs2pr
-        env:
-          # Token is needed for the PHPCS 4.x run against source.
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-
-      # Set Composer up to download only PHPCS from source for PHPCS 4.x.
-      # The source is needed to get the base testcase from PHPCS.
-      # All other jobs can use `auto`, which is Composer's default value.
-      - name: 'Composer: conditionally prefer source for PHPCS 4.x'
-        if: ${{ startsWith( matrix.phpcs_version, '4' ) }}
-        run: composer config preferred-install.squizlabs/php_codesniffer source
 
       - name: 'Composer: adjust CS dependencies (high)'
         if: ${{ matrix.cs_dependencies == 'highest' }}
         run: |
           composer require --no-update --no-scripts squizlabs/php_codesniffer:"${{ env.PHPCS_HIGHEST }}" --no-interaction
           composer require --no-update --no-scripts wp-coding-standards/wpcs:"${{ env.WPCS_HIGHEST }}" --no-interaction
 
-      - name: 'Composer: adjust CS dependencies (4.x)'
-        if: ${{ matrix.phpcs_version }}
-        run: |
-          composer require --no-update --no-scripts squizlabs/php_codesniffer:"${{ matrix.phpcs_version }}" --no-interaction
-
-      - name: 'Composer: conditionally remove PHPCSDevtools for PHPCS 4.x'
-        if: ${{ startsWith( matrix.phpcs_version, '4' ) }}
-        # Remove devtools as it will not (yet) install on PHPCS 4.x.
-        run: composer remove --no-update --dev phpcsstandards/phpcsdevtools --no-interaction
-
       # Install dependencies and handle caching in one go.
       # @link https://github.com/marketplace/actions/install-composer-dependencies
       - name: Install Composer dependencies - normal
@@ -180,7 +155,7 @@ jobs:
       - name: Setup ini config
         id: set_ini
         run: |
-          if [[ "${{ matrix.cs_dependencies }}" != "highest" && "${{ matrix.phpcs_version }}" != "4.0.x-dev" ]]; then
+          if [[ "${{ matrix.cs_dependencies }}" != "highest" ]]; then
             echo 'PHP_INI=error_reporting=E_ALL & ~E_DEPRECATED, display_errors=On' >> $GITHUB_OUTPUT
           else
             echo 'PHP_INI=error_reporting=-1, display_errors=On' >> $GITHUB_OUTPUT