chore(deps): bump @polkadot/api from 1.1.1 to 1.2.1
Bumps [@polkadot/api](https://github.com/polkadot-js/api) from 1.1.1 to 1.2.1.
- [Release notes](https://github.com/polkadot-js/api/releases)
- [Changelog](https://github.com/polkadot-js/api/blob/master/CHANGELOG.md)
- [Commits](https://github.com/polkadot-js/api/compare/v1.1.1...v1.2.1)
Signed-off-by: dependabot-preview[bot] <[email protected]>