[jfx17u] RFR: 8378703: use xcode15 for macos build on jfx17u [v2]

[Johan Vos]

> Bump Xcode version to the same version currently used in head (15.4+1.0)
> Before moving to Xcode 15, we need to solve some build issues. This is tackled in https://github.com/openjdk/jfx17u/pull/254

Johan Vos has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains two additional commits since the last revision:

 - Merge branch 'master' into 8378703-xcode15
 - Bump Xcode version to the same version currently used in head (15.4+1.0)

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

Changes:
  - all: https://git.openjdk.org/jfx17u/pull/255/files
  - new: https://git.openjdk.org/jfx17u/pull/255/files/2dfa10b9..d5b6d20f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jfx17u&pr=255&range=01
 - incr: https://webrevs.openjdk.org/?repo=jfx17u&pr=255&range=00-01

  Stats: 54 lines in 14 files changed: 36 ins; 5 del; 13 mod
  Patch: https://git.openjdk.org/jfx17u/pull/255.diff
  Fetch: git fetch https://git.openjdk.org/jfx17u.git pull/255/head:pull/255

PR: https://git.openjdk.org/jfx17u/pull/255