title: git svn clone update_ref failed for ref, refusing to update ref with bad name
body: <p>I'm trying to migrate my SVN repo to a Git repo. During a <code>git svn clone</code> command I get the following error</p>
  
  <blockquote>
    <p>Unrecognized escape \M passed through in regex; marked by &lt;-- HERE in m/^([0-9a-fA-F]+)</p>
    
    <p>fatal: update_ref failed for ref 'refs/remotes/origin/8.0-R3\MyProject@26482': refusing to update ref with bad name refs/remotes/origin/8.0-R3\MyProject@26482
    update-ref -m r32123 refs/remotes/origin/8.0-R3\MyProject@26482 a48597b7e7a12f9deed97b07b1685994eae7369b: command returned error: 128</p>
  </blockquote>
  
  <p>I think the error is caused due to a backslash in the path.
  I tried ignoring the path using <code>--ignore-paths</code> but it didn't work.</p>