InitLfs: Remove unnecessary empty overridden method

The postRun method has an empty default implementation, so the
override is not necessary.

Change-Id: I01ca06273622caad05462c798bc495002ee5c012
diff --git a/src/main/java/com/googlesource/gerrit/plugins/lfs/InitLfs.java b/src/main/java/com/googlesource/gerrit/plugins/lfs/InitLfs.java
index 89e6238..f44c8d8 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/lfs/InitLfs.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/lfs/InitLfs.java
@@ -36,7 +36,4 @@
   public void run() throws Exception {
     lfs.set(PLUGIN_KEY, name);
   }
-
-  @Override
-  public void postRun() throws Exception {}
 }