In the root directory of a jtreg binaries bundle you find a README file, that is copied from the src/share/doc/javatest/regtest/ directory.

This file contains a "Release Notes." section refering to outdated jtreg 4.2

https://github.com/openjdk/jtreg/blob/0bb8367d17d4f83a83b2d680badb9c25011534d4/src/share/doc/javatest/regtest/README#L14-L18

This section should be updated, either by removing it or by providing a link to the CHANGELOG.md file (which in turn should also be bundled).