build(deps): update league/openapi-psr7-validator requirement from ^0.12 || ^0.14 to ^0.15.2

Updates the requirements on [league/openapi-psr7-validator](https://github.com/thephpleague/openapi-psr7-validator) to permit the latest version.
- [Release notes](https://github.com/thephpleague/openapi-psr7-validator/releases)
- [Commits](https://github.com/thephpleague/openapi-psr7-validator/commits/0.15.2)

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

Author: dependabot-preview[bot]

composer.json

@@ -14,7 +14,7 @@
         "ext-json": "*",
         "cebe/php-openapi": "^1.5",
         "fakerphp/faker": "^1.13",
-        "league/openapi-psr7-validator": "^0.12 || ^0.14",
+        "league/openapi-psr7-validator": "^0.15.2",
         "thecodingmachine/safe": "^1.1"
     },
     "require-dev": {