ignore invalid python versions

Author: lepture

Diff for: .github/workflows/python.yml

@@ -21,7 +21,7 @@ jobs:
       max-parallel: 6
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
-        python: ["2.7", "3.6", "3.7", "3.8", "3.9", "3.10", "pypy2", "pypy3"]
+        python: ["2.7", "3.7", "3.8", "3.9", "3.10", "pypy3"]
 
     steps:
     - uses: actions/checkout@v2