Rust CI workflow

[PaulRBerg]

It might be useful for our V3 Rust projects to have a reusable workflow for running CI checks.

Examples:

• https://github.com/PaulRBerg/rust-template/blob/main/.github/workflows/ci.yml
• https://github.com/sablier-labs/v2-merkle-api/blob/main/.github/workflows/ci.yml