Update PHPUnit from 9.6.31 to 9.6.33 to fix security vulnerability

Co-authored-by: gcatanese <1771700+gcatanese@users.noreply.github.com>

Author: Copilot

composer.json

@@ -18,7 +18,7 @@
   "require-dev": {
     "dms/phpunit-arraysubset-asserts": "0.5.0",
     "friendsofphp/php-cs-fixer": "*",
-    "phpunit/phpunit": "9.6.31",
+    "phpunit/phpunit": "9.6.33",
     "php-coveralls/php-coveralls": "2.7.0",
     "squizlabs/php_codesniffer": "3.10.2"
   },