Replace isAssignableFrom() with isInstance() where feasible

Closes gh-36899

Signed-off-by: Yanming Zhou <zhouyanming@gmail.com>

spring-aop/src/main/java/org/springframework/aop/aspectj/AspectJAfterThrowingAdvice.java

@@ -75,7 +75,7 @@ public class AspectJAfterThrowingAdvice extends AbstractAspectJAdvice
 	 * is only invoked if the thrown exception is a subtype of the given throwing type.
 	 */
 	private boolean shouldInvokeOnThrowing(Throwable ex) {
-		return getDiscoveredThrowingType().isAssignableFrom(ex.getClass());
+		return getDiscoveredThrowingType().isInstance(ex);
 	}
 
 }