Bump anchor-lang from 0.19.0 to 0.20.1

Bumps [anchor-lang](https://github.com/project-serum/anchor) from 0.19.0 to 0.20.1.
- [Release notes](https://github.com/project-serum/anchor/releases)
- [Changelog](https://github.com/project-serum/anchor/blob/master/CHANGELOG.md)
- [Commits](coral-xyz/anchor@v0.19.0...v0.20.1)

---
updated-dependencies:
- dependency-name: anchor-lang
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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