test latest python3 with github actions

Author: ypcrts

.github/workflows/unit-tests.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [2.7, 3.5, 3.6, 3.7, 3.8, 3.9, 3.10, 3.11, 3.12, 3.13, pypy3, pypy2]
+        python-version: ['3.x']
 
     steps:
       - uses: actions/checkout@v2