Exclude annotated tags when importing.

dulwich/porcelain.py

@@ -278,7 +278,7 @@ def clone(source, target=None, bare=False, checkout=None,
         r.refs.import_refs(
             b'refs/tags',
             {n[len(b'refs/tags/'):]: v for (n, v) in remote_refs.items()
-                if n.startswith(b'refs/tags/')})
+                if n.startswith(b'refs/tags/') and not n.endswith(b'^{}')})
         r[b"HEAD"] = remote_refs[b"HEAD"]
         if checkout:
             errstream.write(b'Checking out HEAD\n')