chore(deps): update dependency pytest-cov to v6.2.1 (#817)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [pytest-cov](https://redirect.github.com/pytest-dev/pytest-cov)
([changelog](https://pytest-cov.readthedocs.io/en/latest/changelog.html))
| `==6.2.0` -> `==6.2.1` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/pytest-cov/6.2.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/pypi/pytest-cov/6.2.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/pypi/pytest-cov/6.2.0/6.2.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/pytest-cov/6.2.0/6.2.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>pytest-dev/pytest-cov (pytest-cov)</summary>

###
[`v6.2.1`](https://redirect.github.com/pytest-dev/pytest-cov/blob/HEAD/CHANGELOG.rst#621-2025-06-12)

[Compare
Source](https://redirect.github.com/pytest-dev/pytest-cov/compare/v6.2.0...v6.2.1)

- Added a version requirement for pytest's pluggy dependency (1.2.0,
released 2023-06-21) that has the required new-style hookwrapper API.
-   Removed deprecated license classifier (packaging).
- Disabled coverage warnings in two more situations where they have no
value:

    -   "module-not-measured" in workers
    -   "already-imported" in subprocesses

</details>

---

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requirements-test.txt

@@ -1,6 +1,6 @@
 pytest==8.4.0
 pytest-pep8==1.0.6
-pytest-cov==6.2.0
+pytest-cov==6.2.1
 pytest-aiohttp==1.1.0
 pytest-asyncio==1.0.0
 responses==0.25.7