git: openjdk/jdk: 8315863: [GHA] Update checkout action to use v4

[Christian Stein]

Changeset: b74805d3
Author:    Christian Stein <cstein at openjdk.org>
Date:      2023-09-07 16:15:09 +0000
URL:       https://git.openjdk.org/jdk/commit/b74805d38395ca8be9308d882bf6b84e93714849

8315863: [GHA] Update checkout action to use v4

Reviewed-by: shade

! .github/actions/get-gtest/action.yml
! .github/actions/get-jtreg/action.yml
! .github/workflows/build-cross-compile.yml
! .github/workflows/build-linux.yml
! .github/workflows/build-macos.yml
! .github/workflows/build-windows.yml
! .github/workflows/test.yml