Tests: add pypy3 tests again

Author: leszekhanusz

.github/workflows/tests.yml

@@ -8,7 +8,7 @@ jobs:
     strategy:
       max-parallel: 4
       matrix:
-        python-version: ["3.6", "3.7", "3.8", "3.9-dev"]
+        python-version: ["3.6", "3.7", "3.8", "3.9-dev", "pypy3"]
 
     steps:
     - uses: actions/checkout@v2

tox.ini

@@ -1,7 +1,7 @@
 [tox]
 envlist =
     black,flake8,import-order,mypy,manifest,
-    py{36,37,38,39-dev}
+    py{36,37,38,39-dev,py3}
 
 [pytest]
 markers = asyncio
@@ -12,6 +12,7 @@ python =
     3.7: py37
     3.8: py38
     3.9: py39-dev
+    pypy3: pypy3
 
 [testenv]
 passenv = *
@@ -27,7 +28,7 @@ deps = -e.[test]
 commands =
     pip install -U setuptools
     ; run "tox -- tests -s" to show output for debugging
-    py{36,37,39-dev}: pytest {posargs:tests}
+    py{36,37,39-dev,py3}: pytest {posargs:tests}
     py{38}: pytest {posargs:tests --cov-report=term-missing --cov=gql}
 
 [testenv:black]