Pin dependencies (#298)

Co-authored-by: Renovate Bot <[email protected]>

Author: renovate[bot]

composer.json

@@ -24,10 +24,10 @@
         "psr/http-factory": "^1.0"
     },
     "require-dev": {
-        "friendsofphp/php-cs-fixer": "^3.0",
-        "phpunit/phpunit": "^9.5",
-        "guzzlehttp/psr7": "^2.0",
-        "php-mock/php-mock-phpunit": "^2.6"
+        "friendsofphp/php-cs-fixer": "3.2.1",
+        "phpunit/phpunit": "9.5.10",
+        "guzzlehttp/psr7": "2.1.0",
+        "php-mock/php-mock-phpunit": "2.6.0"
     },
     "autoload": {
         "psr-4": {