Bump thiserror from 1.0.20 to 1.0.21
Bump thiserror from 1.0.20 to 1.0.21

Bumps [thiserror](https://github.com/dtolnay/thiserror) from 1.0.20 to 1.0.21.
- [Release notes](https://github.com/dtolnay/thiserror/releases)
- [Commits](https://github.com/dtolnay/thiserror/compare/1.0.20...1.0.21)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
iovxw/rssbot