ReviewersUtil: Fix candidate list multiplier comment

The multiplier constant was changed in I421420357 but the comment
was not updated at the same time.

Change-Id: If7eaa39719e2f8d8d568445e214f38e4b38965d9

gerrit-server/src/main/java/com/google/gerrit/server/ReviewersUtil.java

diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/ReviewersUtil.java b/gerrit-server/src/main/java/com/google/gerrit/server/ReviewersUtil.java
index 08f879f..410dc5c 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/ReviewersUtil.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/ReviewersUtil.java
@@ -101,7 +101,7 @@
     }
   }
 
-  // Generate a candidate list at 3x the size of what the user wants to see to
+  // Generate a candidate list at 2x the size of what the user wants to see to
   // give the ranking algorithm a good set of candidates it can work with
   private static final int CANDIDATE_LIST_MULTIPLIER = 2;