Chore(deps): Bump dtolnay/rust-toolchain in /.github/actions/setup-rust (#1885)

Bumps [dtolnay/rust-toolchain](https://github.com/dtolnay/rust-toolchain) from 67ef31d5b988238dd797d409d6f9574278e20537 to 2c7215f132e9ebf062739d9130488b56d53c060c.
- [Release notes](https://github.com/dtolnay/rust-toolchain/releases)
- [Commits](https://github.com/dtolnay/rust-toolchain/compare/67ef31d5b988238dd797d409d6f9574278e20537...2c7215f132e9ebf062739d9130488b56d53c060c)

---
updated-dependencies:
- dependency-name: dtolnay/rust-toolchain
  dependency-version: 2c7215f132e9ebf062739d9130488b56d53c060c
  dependency-type: direct:production
...

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