RFR: 8325194: GHA: Add macOS M1 testing [v5]

[George Adams]

> Now that macOS M1 executors are [available in GitHub actions](https://github.blog/changelog/2024-01-30-github-actions-introducing-the-new-m1-macos-runner-available-to-open-source/) it makes sense to move the build to run on M1 (rather than cross-compiled) and also enable testing on the platform.

George Adams has updated the pull request incrementally with one additional commit since the last revision:

  simplify jtreg

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/17694/files
  - new: https://git.openjdk.org/jdk/pull/17694/files/5240aed3..acffbee8

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=17694&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=17694&range=03-04

  Stats: 7 lines in 1 file changed: 0 ins; 6 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/17694.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17694/head:pull/17694

PR: https://git.openjdk.org/jdk/pull/17694