RFR: 8339515: [TestBug] Convert web tests to JUnit 5

[Jay Bhaskar]

Successfully converted web tests from JUnit 4 to JUnit 5, ensuring all tests are fully compliant with the JUnit 5 framework.

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Commit messages:
 - 8339515: [TestBug] Convert web tests to JUnit 5

Changes: https://git.openjdk.org/jfx/pull/1567/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1567&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8339515
  Stats: 1186 lines in 44 files changed: 128 ins; 135 del; 923 mod
  Patch: https://git.openjdk.org/jfx/pull/1567.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1567/head:pull/1567

PR: https://git.openjdk.org/jfx/pull/1567