[REQ][Spring] Be able to filter with API version

Created by: Zomzog

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

I need to generate multiple versions of an API handled by the same service. The version can be provided by a custom header or a custom query param. So I can't use Media-type tricks.

My need is to use the spring capacity of filtering (example can be found here).

This will allow us to generate and deploy each version of each contract without conflict and manage.

Describe the solution you'd like

I want to be able to do something like this

            <plugin>
                <groupId>org.openapitools</groupId>
                <artifactId>openapi-generator-maven-plugin</artifactId>
                <version>5.0.1-SNAPSHOT</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>generate</goal>
                        </goals>
                        <configuration>
                            <inputSpec>src/main/resources/openapi.yaml</inputSpec>
                            <generatorName>spring</generatorName>
                            <apiPackage>org.openapitools.api</apiPackage>
                            <modelPackage>org.openapitools.model</modelPackage>
                            <generateSupportingFiles>false</generateSupportingFiles>
                            <configOptions>
                                <versionType>HEADER</versionType>
                                <versionToken>X-CUSTOM-VERSION</versionToken>
                            </configOptions>
                        </configuration>
                    </execution>
                </executions>
            </plugin>

and get

    @GetMapping(
        value = "/ponies",
        produces = { "application/json" },
        headers = "X-CUSTOM-VERSION=1.0.0"
    )

Describe alternatives you've considered

Media-type and path have been excluded. I don't manage to specify this kind of filtering directly in the OAS3 file.

Additional context