Add missing trailing comma on array

Change-Id: I471d3c78f5897fafd29931d1607f6b0f4c69029a
diff --git a/src/main/java/com/googlesource/gerrit/plugins/avatars/gravatar/GravatarAvatarProvider.java b/src/main/java/com/googlesource/gerrit/plugins/avatars/gravatar/GravatarAvatarProvider.java
index f4bd5b0..29f9ac8 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/avatars/gravatar/GravatarAvatarProvider.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/avatars/gravatar/GravatarAvatarProvider.java
@@ -32,7 +32,7 @@
 public class GravatarAvatarProvider implements AvatarProvider {
 
   private static final char[] HEX = {'0', '1', '2', '3', '4', '5', '6', '7',
-      '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
+      '8', '9', 'a', 'b', 'c', 'd', 'e', 'f',};
 
   private static String hex(byte[] in) {
     StringBuilder r = new StringBuilder(2 * in.length);