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

No, just a missing feature I think

Describe the solution you'd like

In Gitlab, one (or more) milestone(s) can be attached to the release, see this documentation:

https://docs.gitlab.com/user/project/releases/#associate-milestones-with-a-release

It looks like jreleaser doesn't manage this case, I checked the source code to verify it:

https://github.com/jreleaser/jreleaser/blob/v1.19.0/sdks/jreleaser-gitlab-java-sdk/src/main/java/org/jreleaser/sdk/gitlab/GitlabReleaser.java#L297

It would be very nice if jreleaser create the link in the release process.

Describe alternatives you've considered

Call Gitlab API after jreleaser to be able to link release and milestone (with https://docs.gitlab.com/api/releases/#update-a-release).