[jdk21u-dev] RFR: 8357141: Update to use jtreg 7.5.2

[Goetz Lindenmaier]

As we recently updated to 7.5.1, I think we should also go to 7.5.2.

Clean except for the change to test/docs/TEST.ROOT
which was added by [8340818: Add a new jtreg test root to test the generated documentation](https://github.com/openjdk/jdk/commit/07f550b85a3910edd28d8761e2adfb8d6a1352f6) in 24

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Commit messages:
 - backport fe3be498b83e70a9f4739ddad6642c3aa04a97d3

Changes: https://git.openjdk.org/jdk21u-dev/pull/2619/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=2619&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8357141
  Stats: 9 lines in 8 files changed: 0 ins; 0 del; 9 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/2619.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/2619/head:pull/2619

PR: https://git.openjdk.org/jdk21u-dev/pull/2619