Update plugin org.openapi.generator to v7.13.0 (#110)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

settings.gradle.kts

@@ -7,7 +7,7 @@ pluginManagement {
         id("io.micronaut.application").version("4.5.1")
         id("io.freefair.lombok").version("8.13.1")
         id("org.sonarqube").version("6.1.0.5360")
-        id("org.openapi.generator").version("7.12.0")
+        id("org.openapi.generator").version("7.13.0")
 
         id("signing")
         id("maven-publish")