[jdk21u-dev] RFR: 8328244: Convert javax/swing/JSlider/6742358/bug6742358.java applet test to main

[Goetz Lindenmaier]

I backport this for parity with 21.0.9-oracle

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Commit messages:
 - Backport 5f2a92d954ce485d372c3cb3e5118556b1d076c3

Changes: https://git.openjdk.org/jdk21u-dev/pull/2040/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=2040&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8328244
  Stats: 227 lines in 3 files changed: 106 ins; 121 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/2040.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/2040/head:pull/2040

PR: https://git.openjdk.org/jdk21u-dev/pull/2040