chore(deps): update dependency responses to v0.25.8 (#836)

This PR contains the following updates:

| Package | Change | Age | Confidence |
|---|---|---|---|
| [responses](https://redirect.github.com/getsentry/responses)
([changelog](https://redirect.github.com/getsentry/responses/blob/master/CHANGES))
| `==0.25.7` -> `==0.25.8` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/responses/0.25.8?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/responses/0.25.7/0.25.8?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>getsentry/responses (responses)</summary>

###
[`v0.25.8`](https://redirect.github.com/getsentry/responses/blob/HEAD/CHANGES#0258)

[Compare
Source](https://redirect.github.com/getsentry/responses/compare/0.25.7...0.25.8)

- Fix bug where the content type is always recorded as either text/plain
or application/json. See
[#&#8203;770](https://redirect.github.com/getsentry/responses/issues/770)
- Allow asserts on add\_callback() matches. See
[#&#8203;727](https://redirect.github.com/getsentry/responses/issues/727)

</details>

---

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requirements-test.txt

@@ -3,5 +3,5 @@ pytest-pep8==1.0.6
 pytest-cov==6.2.1
 pytest-aiohttp==1.1.0
 pytest-asyncio==1.1.0
-responses==0.25.7
+responses==0.25.8
 pytest_httpserver >= 1.1.2