RFR: 8367017: Remove legacy checks from WrappedToolkitTest and convert from bash

[Sergey Bylokhov]

The Toolkit/Headless/WrappedToolkitTest/WrappedToolkitTest.sh test:
 - Checks the "XToolkit" environment property, which was removed a long time ago
 - Checks the "awt.toolkit" java property, which was also removed a long time ago
Since both have been removed, we can simplify the test and additionally drop the use of the bash script.

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Commit messages:
 - 8367017: Remove legacy checks from WrappedToolkitTest and convert from bash

Changes: https://git.openjdk.org/jdk/pull/27127/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=27127&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8367017
  Stats: 265 lines in 2 files changed: 7 ins; 231 del; 27 mod
  Patch: https://git.openjdk.org/jdk/pull/27127.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27127/head:pull/27127

PR: https://git.openjdk.org/jdk/pull/27127