Update the Rust Tonic crate to use the 0.8 version across all services.
To fix the [[ https://linear.app/comm/issue/ENG-1949/update-rust-tonic-to-08#comment-b88e315a | gRPC generation error ]] the `prost` should be upgraded as well.
Raised at [[ https://phab.comm.dev/D5265#155167 | D5264 ]].
Related Linear task: [[ https://linear.app/comm/issue/ENG-1949/update-rust-tonic-to-08 | ENG-1949 ]]