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

requirements-test.txt

@@ -3,6 +3,6 @@ mock==5.1.0
 pg8000==1.31.2
 pytest==8.3.3
 pytest-asyncio==0.24.0
-pytest-cov==5.0.0
+pytest-cov==6.0.0
 pytest-aiohttp==1.0.5
 SQLAlchemy[asyncio]==2.0.36