GH Actions/tests: safeguard that tests pass in CBF mode

Some tests had sneaked in which would pass in CS mode, but not in CBF mode - at least, not without some tweaks.

This adds a test run of the complete test suite in CBF mode against one PHP version to ensure this can't happen again.

Author: jrfnl

.github/workflows/test.yml

@@ -222,21 +222,28 @@ jobs:
           composer-options: ${{ matrix.php == '8.5' && '--ignore-platform-req=php+' || '' }}
           custom-cache-suffix: $(date -u "+%Y-%m")
 
-      # Note: The code style check is run multiple times against every PHP version
-      # as it also acts as an integration test.
       - name: 'PHPCS: set the path to PHP'
         run: php "bin/phpcs" --config-set php_path php
 
       - name: 'PHPUnit: run the full test suite without code coverage'
         if: ${{ matrix.skip_tests != true }}
         run: php "vendor/bin/phpunit" tests/AllTests.php --no-coverage
 
+      # Do one test run against the complete test suite in CBF mode to ensure all tests can run in CBF mode.
+      - name: 'PHPUnit: run the full test suite without code coverage in CBF mode (PHP 8.3 only)'
+        if: ${{ matrix.php == '8.3' }}
+        run: php "vendor/bin/phpunit" tests/AllTests.php --exclude-group nothing --no-coverage
+        env:
+          PHP_CODESNIFFER_CBF: '1'
+
       - name: 'PHPUnit: run select tests in CBF mode'
-        if: ${{ matrix.skip_tests != true }}
+        if: ${{ matrix.skip_tests != true && matrix.php != '8.3' }}
         run: php "vendor/bin/phpunit" tests/AllTests.php --group CBF --exclude-group nothing --no-coverage
         env:
           PHP_CODESNIFFER_CBF: '1'
 
+      # Note: The code style check is run multiple times against every PHP version
+      # as it also acts as an integration test.
       - name: 'PHPCS: check code style without cache, no parallel'
         if: ${{ matrix.custom_ini == false }}
         run: php "bin/phpcs" --no-cache --parallel=1