Add sleep time to allow test to catch up with events

Author: sungshik

src/test/java/engineering/swat/watch/SingleDirectoryTests.java

@@ -213,6 +213,7 @@ void indexingRescanOnOverflow() throws IOException, InterruptedException {
             Files.writeString(directory.resolve("b.txt"), "bar");
             Files.delete(directory.resolve("c.txt"));
             Files.createFile(directory.resolve("d.txt"));
+            Thread.sleep(TestHelper.NORMAL_WAIT.toMillis());
             // At this point, regular events have been generated for a.txt,
             // b.txt, c.txt, and d.txt by the file system. These events won't be
             // handled by `watch` just yet, though, because the semaphore is
@@ -225,7 +226,6 @@ void indexingRescanOnOverflow() throws IOException, InterruptedException {
 
             var overflow = new WatchEvent(WatchEvent.Kind.OVERFLOW, directory);
             ((EventHandlingWatch) watch).handleEvent(overflow);
-            Thread.sleep(TestHelper.NORMAL_WAIT.toMillis());
             Thread.sleep(TestHelper.LONG_WAIT.toMillis());
             // At this point, the current thread has presumably slept long
             // enough for the `OVERFLOW` event to have been handled by the