Removed unused loadGitLocalRefs() from PhabricatorRepositoryPullEngine

Summary:
rP2b0ad243d179f81baad24ccd9748a4ba59017d25 introduced `private function loadGitLocalRefs()`.
In rPe910c76e65e54a439a0af4735ae89c70076673d5, the only call to `loadGitLocalRefs()` was removed, using `loadGitRemoteRefs()` to load (and compare) both remote and local refs. Thus remove this unused method.

Test Plan: Read/grep the code in `PhabricatorRepositoryPullEngine`.

Reviewers: O1 Blessed Committers, valerio.bozzolan

Reviewed By: O1 Blessed Committers, valerio.bozzolan

Subscribers: tobiaswiese, valerio.bozzolan, Matthew, Cigaryno

Differential Revision: https://we.phorge.it/D25718

src/applications/repository/engine/PhabricatorRepositoryPullEngine.php

@@ -602,22 +602,6 @@ final class PhabricatorRepositoryPullEngine
     return $map;
   }
 
-  private function loadGitLocalRefs(PhabricatorRepository $repository) {
-    $refs = id(new DiffusionLowLevelGitRefQuery())
-      ->setRepository($repository)
-      ->execute();
-
-    $map = array();
-    foreach ($refs as $ref) {
-      $fields = $ref->getRawFields();
-      $map[idx($fields, 'refname')] = $ref->getCommitIdentifier();
-    }
-
-    ksort($map);
-
-    return $map;
-  }
-
   private function logRefDifferences(array $remote, array $local) {
     $all = $local + $remote;