chore(deps): bump solana-rent from 4.1.0 to 4.2.1 (#604)

Bumps [solana-rent](https://github.com/anza-xyz/solana-sdk) from 4.1.0 to 4.2.1.
- [Release notes](https://github.com/anza-xyz/solana-sdk/releases)
- [Commits](https://github.com/anza-xyz/solana-sdk/compare/hash@v4.1.0...rent@v4.2.1)

---
updated-dependencies:
- dependency-name: solana-rent
  dependency-version: 4.2.1
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]