sphinx_multiversion/git: Break long line

sphinx_multiversion/git.py

@@ -48,7 +48,8 @@ def get_all_refs(gitroot):
         yield GitRef(name, commit, source, is_remote, refname, creatordate)
 
 
-def get_refs(gitroot, tag_whitelist, branch_whitelist, remote_whitelist, files=()):
+def get_refs(gitroot, tag_whitelist, branch_whitelist, remote_whitelist,
+             files=()):
     for ref in get_all_refs(gitroot):
         if ref.source == "tags":
             if tag_whitelist is None or not re.match(tag_whitelist, ref.name):