Require to implement AutoCloseable for the classes derived from `Ho…

…stUDFWrapper` (#17727)

This adds the requirement to implement `AutoCloseable`  to the classes derived from `HostUDFWrapper`, forcing them to delete the native UDF instance upon class destruction. Doing so will fix the memory leak issue when the native UDF instance never being destroyed.

Authors:
  - Nghia Truong (https://github.com/ttnghia)

Approvers:
  - Robert (Bobby) Evans (https://github.com/revans2)

URL: #17727

java/src/main/java/ai/rapids/cudf/HostUDFWrapper.java

@@ -24,8 +24,10 @@
  * <p>
  * A new host UDF aggregation implementation must extend this class and override the
  * {@code hashCode} and {@code equals} methods for such purposes.
+ * In addition, since this class implements {@code AutoCloseable}, the {@code close} method must
+ * also be overridden to automatically delete the native UDF instance upon class destruction.
  */
-public abstract class HostUDFWrapper {
+public abstract class HostUDFWrapper implements AutoCloseable {
   public final long udfNativeHandle;
 
   public HostUDFWrapper(long udfNativeHandle) {