chore(deps): update dependency pytest-cov to v6 (#41)

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))
| `5.0.0` -> `6.1.1` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/pytest-cov/6.1.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/pypi/pytest-cov/6.1.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/pypi/pytest-cov/5.0.0/6.1.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/pytest-cov/5.0.0/6.1.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

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

###
[`v6.1.1`](https://redirect.github.com/pytest-dev/pytest-cov/blob/HEAD/CHANGELOG.rst#611-2025-04-05)

[Compare
Source](https://redirect.github.com/pytest-dev/pytest-cov/compare/v6.1.0...v6.1.1)

- Fixed breakage that occurs when `--cov-context` and the `no_cover`
marker are used together.

###
[`v6.1.0`](https://redirect.github.com/pytest-dev/pytest-cov/blob/HEAD/CHANGELOG.rst#610-2025-04-01)

[Compare
Source](https://redirect.github.com/pytest-dev/pytest-cov/compare/v6.0.0...v6.1.0)

- Change terminal output to use full width lines for the coverage
header.
Contributed by Tsvika Shapira in `#&#8203;678
<https://github.com/pytest-dev/pytest-cov/pull/678>`\_.
- Removed unnecessary CovFailUnderWarning. Fixes `#&#8203;675
<https://github.com/pytest-dev/pytest-cov/issues/675>`\_.
- Fixed the term report not using the precision specified via
`--cov-precision`.

###
[`v6.0.0`](https://redirect.github.com/pytest-dev/pytest-cov/blob/HEAD/CHANGELOG.rst#600-2024-10-29)

[Compare
Source](https://redirect.github.com/pytest-dev/pytest-cov/compare/v5.0.0...v6.0.0)

- Updated various documentation inaccuracies, especially on subprocess
handling.
- Changed fail under checks to use the precision set in the coverage
configuration.
    Now it will perform the check just like `coverage report` would.
- Added a `--cov-precision` cli option that can override the value set
in your coverage configuration.
-   Dropped support for now EOL Python 3.8.

</details>

---

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