RFR: JDK-8365423 : [macos26] java/awt/MenuBar/8007006/bug8007006.java fails on macOS 26

[Harshitha Onkar]

Test fails on the macOS 26 because test uses hardcoded location of menu item to click, but on macOS 26 the menu bar is taller and robot misses the menu item by couple of pixels. 

Fix : Screen insets is used to get the y location of menu item Instead of using hardcoded value. 

Additionally test has been cleaned up and frames moved to the center of screen to avoid menubar interactions.

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Commit messages:
 - macOS26 test fix

Changes: https://git.openjdk.org/jdk/pull/27776/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=27776&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8365423
  Stats: 100 lines in 1 file changed: 37 ins; 27 del; 36 mod
  Patch: https://git.openjdk.org/jdk/pull/27776.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27776/head:pull/27776

PR: https://git.openjdk.org/jdk/pull/27776