[jdk21u-dev] RFR: 8328482: Convert and Open source few manual applet test to main based

[Goetz Lindenmaier]

I backport this for parity with 21.0.8-oracle.

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Commit messages:
 - Backport bea9acc55a7b0463a1b0b4dcb557f8ea17d8fe8c

Changes: https://git.openjdk.org/jdk21u-dev/pull/1471/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1471&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8328482
  Stats: 535 lines in 8 files changed: 535 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1471.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1471/head:pull/1471

PR: https://git.openjdk.org/jdk21u-dev/pull/1471