Merge #1585: Testing on minimum-required and latest Python version only

4f4945e Test min and latest Python version only (roshii)

Pull request description:

  Taking the same approach as `bitcoind` version testing, setting only minimum required and latest Python version in CI. Testing so many versions does not bring much added value IMHO.

ACKs for top commit:
  kristapsk:
    ACK 4f4945e

Tree-SHA512: 7678783323828dad9e0899c557077344ba968cc716b6aeccc1f50a4a5eaa23d6b2bf89eb0a607c2e1c31a395e03b26b65187d8ae5386674fc512ae9790cc9560

.github/workflows/unittests.yml

@@ -9,7 +9,7 @@ jobs:
     strategy:
       matrix:
         os: [macos-latest, ubuntu-latest]
-        python-version: ["3.7", "3.8", "3.9", "3.10", "3.11"]
+        python-version: ["3.7", "3.11"]
         bitcoind-version: ["0.18.0", "25.1"]
 
     steps: