upgrade werkzeug to version 3

[alexrashed]

Motivation

This PR upgrades Werkzeug to version 3 and fixes some issues caused by the removal of deprecations (or other breaking changes with version 3).
This PR removes the pin (avoiding the upgrade) added with #9272.

Changes

• Updates minimum version in setup.cfg.
• Fixes some issues which came up with the new major release:
  • Decode headers when populating the WSGI request headers from the ASGI requests and when forwarding requests.
    • Werkzeug's Headers object raises a BadRequestKeyError if a key is not of type str.
    • See pallets/werkzeug@5ff0a57.
  • Removes the usage of charset and encoding_errors on the Map (they have been removed).
    • Also see pallets/werkzeug@5ff0a57 (even though it's not mentioned in the commit message).

Testing

As soon as the pipeline is green again (and the upgrade is tested with LocalStack Pro), this upgrade is safe to be merged.

TODO

• Make sure all tests in the pipeline are 💚
  • I executed a full run (amd64, arm64, community tests) of our Pro pipeline. All 💚.

[github-actions]

LocalStack Community integration with Pro

       2 files  ±0         2 suites  ±0   1h 23m 17s ⏱️ + 13m 14s
2 222 tests ±0  1 725 ✔️ ±0  497 💤 ±0  0 ❌ ±0 
2 223 runs  ±0  1 725 ✔️ ±0  498 💤 ±0  0 ❌ ±0 

Results for commit 0c0b62e. ± Comparison against base commit 6e8915a.

♻️ This comment has been updated with latest results.

[coveralls]

coverage: 83.034% (+0.002%) from 83.032% when pulling 0c0b62e on upgrade-werkzeug-3 into 6e8915a on master.

[dominikschubert]

✔️

[thrau]

LGTM!

just thinking that updating the constraints of core dependencies like this may affect extensions in unexpected ways. not sure what to do about it right now or how to deal with it moving forward, but something we should consider