Fix pylint warning W0108: Lambda may not be necessary

Remove unnecessary usage of lambda.

Change-Id: I06d41933057d60d15d307ee800cca052a44754c6
diff --git a/project.py b/project.py
index cdb4ecf..f72b1c8 100644
--- a/project.py
+++ b/project.py
@@ -1175,7 +1175,7 @@
     cmd = ['fetch', remote.name]
     cmd.append('refs/changes/%2.2d/%d/%d' \
                % (change_id % 100, change_id, patch_id))
-    cmd.extend(map(lambda x: str(x), remote.fetch))
+    cmd.extend(map(str, remote.fetch))
     if GitCommand(self, cmd, bare=True).Wait() != 0:
       return None
     return DownloadedChange(self,