Add a method to set a "not in" WHERE clause in CriteriaQueryBuilder (#1225)

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core/src/main/java/google/registry/persistence/transaction/CriteriaQueryBuilder.java

@@ -62,6 +62,13 @@ public class CriteriaQueryBuilder<T> {
     return where(root.get(fieldName).in(values));
   }
 
+  /**
+   * Adds a WHERE clause to the query specifying that a value must not be in the given collection.
+   */
+  public CriteriaQueryBuilder<T> whereFieldIsNotIn(String fieldName, Collection<?> values) {
+    return where(root.get(fieldName).in(values).not());
+  }
+
   /**
    * Adds a WHERE clause to the query specifying that a collection field must contain a particular
    * value.