Fix issue with older tox versions

Author: Cito

Diff for: tox.ini

@@ -47,9 +47,9 @@ deps =
     pytest-cov>=4.1,<7
     pytest-describe>=2.2,<3
     pytest-timeout>=2.3,<3
-    py3{7,8,9}, pypy39: typing-extensions>=4.7.1,<5
+    py3{7,8,9},pypy39: typing-extensions>=4.7.1,<5
 commands =
     # to also run the time-consuming tests: tox -e py312 -- --run-slow
     # to run the benchmarks: tox -e py312 -- -k benchmarks --benchmark-enable
-    py3{7,8,9,10,11,13}, pypy3{9,10}: pytest tests {posargs}
+    py3{7,8,9,10,11,13},pypy3{9,10}: pytest tests {posargs}
     py312: pytest tests {posargs: --cov-report=term-missing --cov=graphql --cov=tests --cov-fail-under=100}