Update swaggest/json-schema requirement from ^0.12.42 to ^0.12.43

Updates the requirements on [swaggest/json-schema](https://github.com/swaggest/php-json-schema) to permit the latest version.
- [Release notes](https://github.com/swaggest/php-json-schema/releases)
- [Changelog](https://github.com/swaggest/php-json-schema/blob/master/CHANGELOG.md)
- [Commits](swaggest/php-json-schema@v0.12.42...v0.12.43)

---
updated-dependencies:
- dependency-name: swaggest/json-schema
  dependency-type: direct:production
...

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

composer.json

@@ -17,7 +17,7 @@
     "require": {
         "php": ">=7.4",
         "seld/jsonlint": "^1.11",
-        "swaggest/json-schema": "^0.12.42",
+        "swaggest/json-schema": "^0.12.43",
         "symfony/polyfill-php81": "^1.31",
         "ext-json": "*",
         "ext-libxml": "*",