Minor, make sure we release locks in pull daemon if we fail in unusual ways

Summary: A user is reporting a re-lock in this daemon, which I can't
reproduce, but might be possible if this throws. Stop it from throwing in
a way which evades unlock.

See: <https://github.com/facebook/phabricator/issues/476>

Auditors: btrahan

src/applications/repository/daemon/PhabricatorRepositoryPullLocalDaemon.php

@@ -144,11 +144,10 @@ final class PhabricatorRepositoryPullLocalDaemon
             $lock = PhabricatorGlobalLock::newLock($lock_name);
             $lock->lock();
 
+            try {
               $repository->writeStatusMessage(
                 PhabricatorRepositoryStatusMessage::TYPE_NEEDS_UPDATE,
                 null);
-
-            try {
               $this->discoverRepository($repository);
               $repository->writeStatusMessage(
                 PhabricatorRepositoryStatusMessage::TYPE_FETCH,