Using the "tag" function on a project build when a local subdirectory has been set for the GIT repo will lead to error:

Error taggin repo 'master' : org.eclipse.jgit.errors.RepositoryNotFoundException: repository not found: /var/lib/jenkins/jobs/my_project/workspace
hudson.plugins.git.GitException: org.eclipse.jgit.errors.RepositoryNotFoundException: repository not found: /var/lib/jenkins/jobs/my_project/workspace
at org.jenkinsci.plugins.gitclient.JGitAPIImpl.tag(JGitAPIImpl.java:201)
at hudson.plugins.git.GitTagAction$TagWorkerThread$1.invoke(GitTagAction.java:194)
at hudson.plugins.git.GitTagAction$TagWorkerThread$1.invoke(GitTagAction.java:181)
at hudson.FilePath.act(FilePath.java:905)
at hudson.FilePath.act(FilePath.java:878)
at hudson.plugins.git.GitTagAction$TagWorkerThread.perform(GitTagAction.java:181)
at hudson.model.TaskThread.run(TaskThread.java:127)
Caused by: org.eclipse.jgit.errors.RepositoryNotFoundException: repository not found: /var/lib/jenkins/jobs/my_project/workspace
at org.eclipse.jgit.lib.BaseRepositoryBuilder.build(BaseRepositoryBuilder.java:575)
at org.eclipse.jgit.api.Git.open(Git.java:113)
at org.eclipse.jgit.api.Git.open(Git.java:97)
at org.jenkinsci.plugins.gitclient.JGitAPIImpl.tag(JGitAPIImpl.java:198)
... 6 more
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