Bump minimal supported pytest version

Author: asvetlov

.github/workflows/main.yml

@@ -56,6 +56,7 @@ jobs:
     strategy:
       matrix:
         python-version: ['3.7', '3.8', '3.9', '3.10']
+        pytest-version: [6.1.0, 7.0.0rc1]
 
     steps:
     - uses: actions/checkout@v2

setup.cfg

@@ -37,7 +37,7 @@ setup_requires =
   setuptools_scm >= 6.2
 
 install_requires =
-  pytest >= 5.4.0
+  pytest >= 6.1.0
 
 [options.extras_require]
 testing =