in jenkins-pipeline-shared-libraries/vars/githubscm.groovy [223:238]
def tagRepository(String tagName, String buildTag = '') {
def currentCommit = getCommit()
def tagMessageEnding = buildTag ? " in build \"${buildTag}\"." : '.'
def tagMessage = "Tagged by Jenkins${tagMessageEnding}"
sh "git tag -a '${tagName}' -m '${tagMessage}'"
println """
-------------------------------------------------------------
[INFO] Tagged current repository
-------------------------------------------------------------
Commit: ${currentCommit}
Tagger: ${env.GIT_COMMITTER_NAME} (${env.GIT_COMMITTER_EMAIL})
Tag: ${tagName}
Tag Message: ${tagMessage}
-------------------------------------------------------------
"""
}