Update squizlabs/php_codesniffer requirement from ^3.6 to ^3.7

Updates the requirements on [squizlabs/php_codesniffer](https://github.com/squizlabs/PHP_CodeSniffer) to permit the latest version.
- [Release notes](https://github.com/squizlabs/PHP_CodeSniffer/releases)
- [Commits](squizlabs/PHP_CodeSniffer@3.6.0...3.7.1)

---
updated-dependencies:
- dependency-name: squizlabs/php_codesniffer
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>

composer.json

@@ -44,7 +44,7 @@
     "phpspec/prophecy-phpunit": "^2.0",
     "phpstan/phpstan": "^1.7",
     "phpunit/phpunit": "^9.5",
-    "squizlabs/php_codesniffer": "^3.6"
+    "squizlabs/php_codesniffer": "^3.7"
   },
   "provide": {
     "psr/http-message-implementation": "1.0",