Remove trailing blank lines

flake8 reports:

  W391 blank line at end of file

Change-Id: I5498b2de2d1268d4f1f4b9e1760f9fa93a6da4cd
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/254594
Tested-by: David Pursehouse <dpursehouse@collab.net>
Reviewed-by: Mike Frysinger <vapier@google.com>

manifest_xml.py

@@ -1134,4 +1134,3 @@ class GitcManifest(XmlManifest):
     """Output GITC Specific Project attributes"""
     if p.old_revision:
       e.setAttribute('old-revision', str(p.old_revision))
-

subcmds/sync.py

@@ -1265,4 +1265,3 @@ class PersistentTransport(xmlrpc.client.Transport):
 
   def close(self):
     pass
-