Minor Javadoc update

spring-web/src/test/java/org/springframework/http/server/reactive/AbstractHttpHandlerIntegrationTests.java

@@ -79,6 +79,14 @@ public abstract class AbstractHttpHandlerIntegrationTests {
 	/**
 	 * Return an interval stream of with n number of ticks and buffer the
 	 * emissions to avoid back pressure failures (e.g. on slow CI server).
+	 *
+	 * <p>Use this method as follows:
+	 * <ul>
+	 * <li>Tests that verify N number of items followed by verifyOnComplete()
+	 * should set the number of emissions to N.
+	 * <li>Tests that verify N number of items followed by thenCancel() should
+	 * set the number of buffered to an arbitrary number greater than N.
+	 * </ul>
 	 */
 	public static Flux<Long> interval(Duration period, int count) {
 		return Flux.interval(period).take(count).onBackpressureBuffer(2);