add minor version component to windows pypy python version

Author: RonnyPfannschmidt

.github/workflows/main.yml

@@ -40,7 +40,7 @@ jobs:
             os: windows-latest
             tox_env: "py310"
           - name: "windows-pypy3"
-            python: "pypy3"
+            python: "pypy3.7"
             os: windows-latest
             tox_env: "pypy3.7"
           - name: "ubuntu-py37-pytestmain"