[jfx21u] RFR: 8368572: Update WebKit to 623.1 [v2]

[Johan Vos]

> Hi all,
> 
> This pull request contains a backport of commit [422d3a95](https://github.com/openjdk/jfx/commit/422d3a954d531c9cca32b1401b5937b05b1b07fa) from the [openjdk/jfx](https://git.openjdk.org/jfx) repository.
> 
> The commit being backported was authored by Hima Bindu Meda on 21 Jan 2026 and was reviewed by Kevin Rushforth, Joeri Sykora and Johan Vos.
> 
> Thanks!

Johan Vos has updated the pull request incrementally with one additional commit since the last revision:

  Adapt tests to junit 4 API

-------------

Changes:
  - all: https://git.openjdk.org/jfx21u/pull/116/files
  - new: https://git.openjdk.org/jfx21u/pull/116/files/b459b46f..81a4aebb

Webrevs:
 - full: Webrev is not available because diff is too large
 - incr: https://webrevs.openjdk.org/?repo=jfx21u&pr=116&range=00-01

  Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jfx21u/pull/116.diff
  Fetch: git fetch https://git.openjdk.org/jfx21u.git pull/116/head:pull/116

PR: https://git.openjdk.org/jfx21u/pull/116