[REQ] Modified pom.xml files to reduce the build time

Is your feature request related to a problem? Please describe.

I noticed that this is a Maven project, so I checked all of the pom.xml file and found that there are two dependencies :
①
Relative paths: openapi-generator/samples/server/petstore/jaxrs-cxf-test-data/pom.xml
Dependency: { Name: org.openapitools/openapi-generator, Version Specifier: 5.2.0-SNAPSHOT }
②
Relative paths: openapi-generator/samples/server/petstore/kotlin/vertx/pom.xml
Dependency: {Name: org.jetbrains.kotlinx/kotlinx-coroutines-core, Version Specifier: RELEASE}

we know that RELEASE/LATEST/SNAPSHOT dependence means that every time the project is built, the dependency needs to find the latest version, which increases the cost of the build.

Describe the solution you'd like

It helps to have a specific version. So I have modified the of the two dependencies as follows:
①
Relative paths: openapi-generator/samples/server/petstore/jaxrs-cxf-test-data/pom.xml
Dependency: { Name: org.openapitools/openapi-generator, Version Specifier: 5.2.0-SNAPSHOT } ------> 5.2.0

②
Relative paths: openapi-generator/samples/server/petstore/kotlin/vertx/pom.xml
Dependency: {Name: org.jetbrains.kotlinx/kotlinx-coroutines-core, Version Specifier: RELEASE} ------> 1.5.1-native-mt

Inspect the dependency declarations in openapi-generator/samples/server/petstore/jaxrs-cxf-test-data/pom.xml and openapi-generator/samples/server/petstore/kotlin/vertx/pom.xml. Build the affected sample modules and confirm both dependencies use fixed versions rather than SNAPSHOT or RELEASE resolution.