chore(deps): update dependency pytest-cov to v6

Author: anaconda-renovate[bot]

requirements.txt

@@ -5,7 +5,7 @@ importlib-metadata==8.5.0
 packaging
 psutil==6.1.0
 pytest==8.3.3
-pytest-cov==5.0.0
+pytest-cov==6.3.0
 pytest-mock==3.14.1
 pytest-mypy==0.10.3
 pythonanywhere_core==0.2.4