Update uvicorn requirement from <0.19.1 to <0.21.2 in /requirements (#17314)
Updates the requirements on [uvicorn](https://github.com/encode/uvicorn) to permit the latest version.
- [Release notes](https://github.com/encode/uvicorn/releases)
- [Changelog](https://github.com/encode/uvicorn/blob/master/CHANGELOG.md)
- [Commits](https://github.com/encode/uvicorn/compare/0.0.1...0.21.1)
---
updated-dependencies:
- dependency-name: uvicorn
dependency-type: direct:production
...
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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
(cherry picked from commit 09ae070d2d648d3b2c59183cd6ec2236d21d6a98)