RFR: 8274597: Some of the dnd tests time out and fail intermittently

[Manukumar V S]

These dnd tests fails with a time out intermittently in some machines(mostly Windows 11) which creates frequent noise in CI.
1. java/awt/dnd/AcceptDropMultipleTimes/AcceptDropMultipleTimes.java
2. java/awt/dnd/DropTargetEnterExitTest/MissedDragExitTest.java
3. java/awt/dnd/DropTargetEnterExitTest/ExtraDragEnterTest.java

Issue :
These tests are using the Util.drag() method and there was no robot.delay() added between different mouse actions in this method. This could potentially make tests using this method unstable.

Fix:
Adding a small auto delay of 100ms to fix this.

Testing:
1. All the three tests are run 15 times per platform.
2. All the tests in java/awt/dnd package run 5 times per platform
3. All the three tests are run 5 times specifically on Windows 11 platform.

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Commit messages:
 - 8274597: Some of the dnd tests time out and fail intermittently

Changes: https://git.openjdk.java.net/jdk/pull/8316/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8316&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8274597
  Stats: 9 lines in 1 file changed: 8 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8316.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8316/head:pull/8316

PR: https://git.openjdk.java.net/jdk/pull/8316