add version 6.6.3

server/src/main/java/org/elasticsearch/Version.java

@@ -122,6 +122,8 @@ public class Version implements Comparable<Version>, ToXContentFragment {
     public static final Version V_6_6_1 = new Version(V_6_6_1_ID, org.apache.lucene.util.Version.LUCENE_7_6_0);
     public static final int V_6_6_2_ID = 6060299;
     public static final Version V_6_6_2 = new Version(V_6_6_2_ID, org.apache.lucene.util.Version.LUCENE_7_6_0);
+    public static final int V_6_6_3_ID = 6060399;
+    public static final Version V_6_6_3 = new Version(V_6_6_3_ID, org.apache.lucene.util.Version.LUCENE_7_6_0);
     public static final int V_6_7_0_ID = 6070099;
     public static final Version V_6_7_0 = new Version(V_6_7_0_ID, org.apache.lucene.util.Version.LUCENE_7_7_0);
     public static final int V_7_0_0_ID = 7000099;
@@ -152,6 +154,8 @@ public class Version implements Comparable<Version>, ToXContentFragment {
                 return V_7_0_0;
             case V_6_7_0_ID:
                 return V_6_7_0;
+            case V_6_6_3_ID:
+                return V_6_6_3;
             case V_6_6_2_ID:
                 return V_6_6_2;
             case V_6_6_1_ID: