Replace anonymous class with list method

Change-Id: I29cd4de5ec298efd569efc1499f3842eec6e9976

src/main/java/com/googlesource/gerrit/plugins/importer/ReplayRevisionsStep.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/importer/ReplayRevisionsStep.java b/src/main/java/com/googlesource/gerrit/plugins/importer/ReplayRevisionsStep.java
index 4eafe91..85e1a07 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/importer/ReplayRevisionsStep.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/importer/ReplayRevisionsStep.java
@@ -40,8 +40,6 @@
 
 import java.io.IOException;
 import java.util.ArrayList;
-import java.util.Collections;
-import java.util.Comparator;
 import java.util.List;
 
 class ReplayRevisionsStep {
@@ -161,12 +159,7 @@
   }
 
   private static void sortRevisionInfoByNumber(List<RevisionInfo> list) {
-    Collections.sort(list, new Comparator<RevisionInfo>() {
-      @Override
-      public int compare(RevisionInfo a, RevisionInfo b) {
-        return a._number - b._number;
-      }
-    });
+    list.sort((a, b) -> a._number - b._number);
   }
 
   private void updateRef(Repository repo, PatchSet ps)