py-requests: update to 2.28.1.

Fixes PR 56915.

2.28.1 (2022-06-29)
-------------------

**Improvements**

- Speed optimization in `iter_content` with transition to `yield from`. (#6170)

**Dependencies**

- Added support for chardet 5.0.0 (#6179)
- Added support for charset-normalizer 2.1.0 (#6169)

2.28.0 (2022-06-09)
-------------------

**Deprecations**

- ⚠️ Requests has officially dropped support for Python 2.7. ⚠️ (#6091)
- Requests has officially dropped support for Python 3.6 (including pypy3.6). (#6091)

**Improvements**

- Wrap JSON parsing issues in Request's JSONDecodeError for payloads without
  an encoding to make `json()` API consistent. (#6097)
- Parse header components consistently, raising an InvalidHeader error in
  all invalid cases. (#6154)
- Added provisional 3.11 support with current beta build. (#6155)
- Requests got a makeover and we decided to paint it black. (#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. (#6074)
- Fixed urllib3 exception leak, wrapping `urllib3.exceptions.SSLError` with
  `requests.exceptions.SSLError` for `content` and `iter_content`. (#6057)
- Fixed issue where invalid Windows registry entires caused proxy resolution
  to raise an exception rather than ignoring the entry. (#6149)
- Fixed issue where entire payload could be included in the error message for
  JSONDecodeError. (#6036)

(wiz)