Update pytest from 6.1.1 to 8.3.1

Author: pyup-bot

requirements-dev.txt

@@ -12,7 +12,7 @@ py==1.9.0
 pycodestyle==2.6.0
 pyflakes==2.2.0
 pyparsing==2.4.7
-pytest==6.1.1
+pytest==8.3.1
 pytest-cov==2.10.1
 pytest-mock==3.3.1
 six==1.15.0