deps: update dependency requests to v2.28.1 (#857)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [requests](https://requests.readthedocs.io) ([source](https://github.com/psf/requests), [changelog](https://github.com/psf/requests/blob/master/HISTORY.md)) | `==2.27.1` -> `==2.28.1` | [![age](https://badges.renovateapi.com/packages/pypi/requests/2.28.1/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/pypi/requests/2.28.1/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/pypi/requests/2.28.1/compatibility-slim/2.27.1)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/pypi/requests/2.28.1/confidence-slim/2.27.1)](https://docs.renovatebot.com/merge-confidence/) |

---

### Release Notes

<details>
<summary>psf/requests</summary>

### [`v2.28.1`](https://github.com/psf/requests/blob/HEAD/HISTORY.md#&#8203;2281-2022-06-29)

[Compare Source](https://github.com/psf/requests/compare/v2.28.0...v2.28.1)

**Improvements**

-   Speed optimization in `iter_content` with transition to `yield from`. ([#&#8203;6170](https://github.com/psf/requests/issues/6170))

**Dependencies**

-   Added support for chardet 5.0.0 ([#&#8203;6179](https://github.com/psf/requests/issues/6179))
-   Added support for charset-normalizer 2.1.0 ([#&#8203;6169](https://github.com/psf/requests/issues/6169))

### [`v2.28.0`](https://github.com/psf/requests/blob/HEAD/HISTORY.md#&#8203;2280-2022-06-09)

[Compare Source](https://github.com/psf/requests/compare/v2.27.1...v2.28.0)

**Deprecations**

-   ⚠️ Requests has officially dropped support for Python 2.7. ⚠️ ([#&#8203;6091](https://github.com/psf/requests/issues/6091))
-   Requests has officially dropped support for Python 3.6 (including pypy3.6). ([#&#8203;6091](https://github.com/psf/requests/issues/6091))

**Improvements**

-   Wrap JSON parsing issues in Request's JSONDecodeError for payloads without
    an encoding to make `json()` API consistent. ([#&#8203;6097](https://github.com/psf/requests/issues/6097))
-   Parse header components consistently, raising an InvalidHeader error in
    all invalid cases. ([#&#8203;6154](https://github.com/psf/requests/issues/6154))
-   Added provisional 3.11 support with current beta build. ([#&#8203;6155](https://github.com/psf/requests/issues/6155))
-   Requests got a makeover and we decided to paint it black. ([#&#8203;6095](https://github.com/psf/requests/issues/6095))

**Bugfixes**

-   Fixed bug where setting `CURL_CA_BUNDLE` to an empty string would disable
    cert verification. All Requests 2.x versions before 2.28.0 are affected. ([#&#8203;6074](https://github.com/psf/requests/issues/6074))
-   Fixed urllib3 exception leak, wrapping `urllib3.exceptions.SSLError` with
    `requests.exceptions.SSLError` for `content` and `iter_content`. ([#&#8203;6057](https://github.com/psf/requests/issues/6057))
-   Fixed issue where invalid Windows registry entires caused proxy resolution
    to raise an exception rather than ignoring the entry. ([#&#8203;6149](https://github.com/psf/requests/issues/6149))
-   Fixed issue where entire payload could be included in the error message for
    JSONDecodeError. ([#&#8203;6036](https://github.com/psf/requests/issues/6036))

</details>

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