RFR: 8317288: [macos] java/awt/Window/Grab/GrabTest.java: Press on the outside area didn't cause ungrab

[Alisen Chung]

Added delays to stabilize test, test passes 50 times consecutively

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Commit messages:
 - added delays to stabilize test

Changes: https://git.openjdk.org/jdk/pull/16867/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16867&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8317288
  Stats: 56 lines in 1 file changed: 34 ins; 6 del; 16 mod
  Patch: https://git.openjdk.org/jdk/pull/16867.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16867/head:pull/16867

PR: https://git.openjdk.org/jdk/pull/16867