Index redemptionHistoryEntry on LrpToken

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=132323443

java/google/registry/model/domain/LrpToken.java

@@ -55,6 +55,7 @@ public class LrpToken extends BackupGroupRoot implements Buildable {
    * The key of the history entry for which the token was used. Given LRP is a domain application
    * phase, this should always be a {@link Type#DOMAIN_APPLICATION_CREATE}.
    */
+  @Index
   Key<HistoryEntry> redemptionHistoryEntry;
   
   public String getToken() {