Missing config generateApi from openapi-generator-maven-plugin

[mbard]

In the openapi-generator-maven-plugin, it is possible to set generateApi=false to generate only the models without the API.

We want to write the API manually but generate the models automatically.

It would be great if this option were exposed in the configuration as:

quarkus.openapi-generator.codegen.spec.<file>.generate_api=false

[hbelmiro]

@mbard this feature was added last week in #897.