The git-plugin doesn't tags as it always uses refs/heads as a prefix

https://github.com/jenkinsci/git-plugin/blob/master/src/main/java/jenkins/plugins/git/AbstractGitSCMSource.java#L417

JENKINS-34395 is similar but the resolution for this might be different.

One option would be to allow users to override the default ref prefix.  Alternatively we could allow multiple user defined ref prefixes in the same way they specify ref specs.