RFR: 8315863: [GHA] Update checkout action to use v4

[Aleksey Shipilev]

On Thu, 7 Sep 2023 16:27:18 GMT, Christian Stein <cstein at openjdk.org> wrote:

> > Please wait for GHA to complete before integrating GHA patches!
> 
> Yes, sure. Next time, I'll wait for completion - this time, I checked that `actions/checkout at v4` steps were successfully run in https://github.com/openjdk/jdk/pull/15620/checks

Yeah, the problem with some GH action steps is that they have "epilog" steps that run at the end of the pipe. So when changing GH action stuff, it is important to see that all steps have completed, which usually means the complete run.

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PR Comment: https://git.openjdk.org/jdk/pull/15620#issuecomment-1710457002