Fix incorrect versions error (ForbiddenThisUseContexts)

PHPCompatibility erroneously flags the use of $this in enumerations.
Commit 5e248cf moved disabling of this error check to .github/workflows/main.yml
Hence, `composer versions` and `composer check` should also exclude this check.

Author: m7913d

composer.json

@@ -47,7 +47,7 @@
         "check": [
             "./bin/check-phpdoc-types",
             "phpcs samples/ src/ tests/ --report=checkstyle",
-            "phpcs samples/ src/ tests/ --standard=PHPCompatibility --runtime-set testVersion 8.0- -n",
+            "phpcs samples/ src/ tests/ --standard=PHPCompatibility --runtime-set testVersion 8.0- --exclude=PHPCompatibility.Variables.ForbiddenThisUseContexts -n",
             "php-cs-fixer fix --ansi --dry-run --diff",
             "phpunit --color=always",
             "phpstan analyse --ansi --memory-limit=2048M"
@@ -61,7 +61,7 @@
             "php-cs-fixer fix"
         ],
         "versions": [
-            "phpcs samples/ src/ tests/ --standard=PHPCompatibility --runtime-set testVersion 8.0- -n"
+            "phpcs samples/ src/ tests/ --standard=PHPCompatibility --runtime-set testVersion 8.0- --exclude=PHPCompatibility.Variables.ForbiddenThisUseContexts -n"
         ]
     },
     "require": {