!39 and !40 changed the CI to use a _toolchain_ file.

however, having `default` as the `$.profile` causes extra useless components to be installed.

this MR sets the `$.profile` to `minimal` in the _toolchain_ file and the `$.components` to `rustfmt` and `clippy`.

fix the toolchain version of Rust with `rust-toolchain.toml`.

this is to avoid having things like `cargo clippy` behaving differently locally and in the remote CI.
> **Note**  
> see https://gitlab.isae-supaero.fr/dragoon/komodo/-/jobs/12875 which fails with Rust 1.72 but works locally with Rust 1.75