Update dependency pytest-cov to v7 (#739)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

poetry.lock

@@ -64,7 +64,7 @@ coverage = "^7.3.4"
 coverage-badge = "^1.1.0"
 cryptography = ">=44.0.1"
 pytest-html = "^4.1.1"
-pytest-cov = "^4.0.0"
+pytest-cov = "^7.0.0"
 marshmallow = ">=3.20,<4.0"
 
 [tool.black]