build(deps-dev): bump phpunit/phpunit from 9.6.15 to 9.6.33 (#210)

Author: dependabot[bot]

composer.json

@@ -15,7 +15,7 @@
         "squizlabs/php_codesniffer": "^3.10.3"
     },
     "require-dev": {
-        "phpunit/phpunit": "^9.6.15"
+        "phpunit/phpunit": "^9.6.33"
     },
     "autoload": {
         "psr-4": {