Cleanup tox config

Author: moggers87

.github/workflows/tests.yml

@@ -24,7 +24,7 @@ jobs:
         with:
           python-version: ${{ matrix.python-version }}
       - name: Install tox
-        run: pip install "tox<4" tox-gh-actions
+        run: pip install tox
       - name: Run tox
         run: tox
       - name: Upload coverage to Codecov

tox.ini

@@ -58,12 +58,3 @@ skip_glob =
     versioneer.py
     tests/*
     salmon/_vendor
-
-[gh-actions]
-python =
-    3.7: py37
-    3.8: py38
-    3.9: py39
-    3.10: py310
-    pypy-3.6: pypy3
-    pypy-3.7: pypy3