RFR: 8075917: The regression-swing case failed as the text on label is not painted red with the GTK L&F [v6]

[Abhishek Kumar]

> JLabel text is not painted with the LAF defined foreground color in GTK LAF. In GTK LAF the foreground color is retrieved by using native system APIs. Fix is to return the foreground color if it is set by LAF defined property otherwise return the default color by calling native APIs.
> Applet based test has been converted to automatic test and check for all installed LAFs. CI testing is green for test suite and individual test. Link attached in JBS.

Abhishek Kumar has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains seven additional commits since the last revision:

 - Revert back the product fix and update test to skip GTK L&F
 - Merge
 - separate method to get LAF defined color
 - extended fix for disabled checkbox and radiobutton
 - Headful tag revert back and condition check for nimbus
 - jtreg tag headful removed
 - JLable foreground color fix for GTK LAF

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Changes:
  - all: https://git.openjdk.org/jdk/pull/17763/files
  - new: https://git.openjdk.org/jdk/pull/17763/files/360e21e8..56268d41

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=17763&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=17763&range=04-05

  Stats: 1432245 lines in 12034 files changed: 312659 ins; 679637 del; 439949 mod
  Patch: https://git.openjdk.org/jdk/pull/17763.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17763/head:pull/17763

PR: https://git.openjdk.org/jdk/pull/17763