Update pytest from 6.2.2 to 8.1.0

requirements_dev.txt

@@ -10,7 +10,7 @@ Sphinx==3.5.3
 sphinx-rtd-theme==0.5.1
 cryptography==3.4.7
 PyYAML==5.4.1
-pytest==6.2.2
+pytest==8.1.0
 pytest-cov==2.11.1
 pytest-runner==5.3.0
 codecov==2.1.11