Merge #1693: CI: Use x64 not arm64 macOS

39720a8 CI: Use x64 not arm64 macOS (Kristaps Kaupe)

Pull request description:

  ARM (M1) GitHub runner doesn't have Python 3.8 available. EOL of 3.8 is 31 Oct 2024, would be good to continue support, unless there are some bigger reasons to drop it sooner.

  And macos-latest was recently changed to M1, see
  <https://docs.github.com/en/actions/using-github-hosted-runners/about-github-hosted-runners/about-github-hosted-runners#standard-github-hosted-runners-for-public-repositories>.

  This fixes current non-random always happening CI failures.

Top commit has no ACKs.

Tree-SHA512: 158c85b82c9a11dbaecfa4dbe872f835f80b41f4efa42529d78f5085852c9366f1029890d5edc7724d578cc67dca06a7e983f179e6c853d04f5f83f8083babd3

.github/workflows/unittests.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [macos-latest, ubuntu-latest]
+        os: [macos-13, ubuntu-latest]
         python-version: ["3.8", "3.11"]
         bitcoind-version: ["0.18.0", "26.0"]