Fix javadoc placement

The prior placement was error prone.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=146825173

java/google/registry/model/registry/Registry.java

@@ -79,11 +79,11 @@ public class Registry extends ImmutableObject implements Buildable {
   @Parent
   Key<EntityGroupRoot> parent = getCrossTldKey();
 
-  @Id
   /**
    * The canonical string representation of the TLD associated with this {@link Registry}, which
    * is the standard ASCII for regular TLDs and punycoded ASCII for IDN TLDs.
    */
+  @Id
   String tldStrId;
 
   /**