Add test for require global install for PHPUnit 12

Author: samsonasik

.github/workflows/compat_tests.yaml.yml

@@ -36,6 +36,12 @@ jobs:
                         name: 'Rector dev + PHPUnit 12'
                         run: composer require "phpunit/phpunit:12.*" "rector/rector:dev-main" -W
                         php: 8.3
+                    -
+                        name: 'Rector dev + PHPUnit 12 global install'
+                        run: |
+                            composer global require --dev "phpunit/phpunit:12.*" -W
+                            composer require --dev "rector/rector:dev-main" -W
+                        php: 8.3
 
         name: ${{ matrix.actions.name }}