[jdk17u-dev] RFR: 8325194: GHA: Add macOS M1 testing [v2]

[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.
> 
> Applies cleanly other than the following:
> 
> - `.github/actions/get-jtreg/action.yml` I also integrated https://github.com/openjdk/jdk/commit/3c91b59ef9c992718d73f2fc9fa50ad2ead78208 as it caused a regression in tip
> - `make/conf/github-actions.conf` having the obvious difference in version numbers for the boot JDK (I also took the liberty of reordering them to be consistent with tip)

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

  Update action.yml

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

Changes:
  - all: https://git.openjdk.org/jdk17u-dev/pull/2697/files
  - new: https://git.openjdk.org/jdk17u-dev/pull/2697/files/26b65e26..fe4ab64f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2697&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2697&range=00-01

  Stats: 3 lines in 1 file changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2697.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2697/head:pull/2697

PR: https://git.openjdk.org/jdk17u-dev/pull/2697