title: TeamCity doesn't fetch tags
body: <p>I'm building GitHub pull requests in TeamCity. I'm setting the branch specification in git VCS root to <code>+:refs/(pull/*)/head</code>. I'm checking out the sources on agent.</p>
  
  <p>With such setup I see that TeamCity doesn't fetch tags - the .git/refs/tags folder is empty. </p>
  
  <p>Why is that?</p>