Feature request: accept --manifest-path

[CAD97]

Notably, this will allow cargo-msrv to run under cargo-hack for use in workspaces and to benefit from cargo-hack's detach-from-workspace implementation.

Specifically, I'd love to be able to cargo hack --workspace minimal-versions msrv verify -- cargo check --all-features, but this ends up running cargo msrv verify --manifest-path subcrate\Cargo.toml -- cargo check --all-features which cargo-msrv then rejects.

The desired behavior is fairly simple: retrieve the rust-version key from the given manifest path, and then forward the --manifest-path argument to the check invocation.

Running under cargo-hack also gives workspace support for free.

[foresterre]

Sounds great! I'll add it soon!

[foresterre]

I've tested #420 with cargo-hack on a repo with a workspace (*), which seems to give the desired results.

Will be included in cargo-msrv 0.16. Thanks for the request!

Output of `cargo hack --workspace msrv verify -- cargo check --all-features`

sic on  main [$] is 📦 v0.20.0 via 🦀 v1.62.0 took 2s
❯ cargo hack --workspace msrv verify -- cargo check --all-features
info: running cargo msrv verify -- cargo check --all-features on sic_cli_ops (1/8)
[Meta] cargo-msrv 0.15.1 (8dcc466)

Compatibility Check #1: Rust 1.56.1
[OK] Is compatible

info: running cargo msrv verify -- cargo check --all-features on sic_image_engine (2/8)
[Meta] cargo-msrv 0.15.1 (8dcc466)

Compatibility Check #1: Rust 1.56.1
[OK] Is compatible

info: running cargo msrv verify -- cargo check --all-features on sic_core (3/8)
[Meta] cargo-msrv 0.15.1 (8dcc466)

Compatibility Check #1: Rust 1.56.1
[OK] Is compatible

info: running cargo msrv verify -- cargo check --all-features on sic_io (4/8)
[Meta] cargo-msrv 0.15.1 (8dcc466)

Compatibility Check #1: Rust 1.56.1
[OK] Is compatible

info: running cargo msrv verify -- cargo check --all-features on sic_testing (5/8)
[Meta] cargo-msrv 0.15.1 (8dcc466)

Compatibility Check #1: Rust 1.56.1
[OK] Is compatible

info: running cargo msrv verify -- cargo check --all-features on sic_parser (6/8)
[Meta] cargo-msrv 0.15.1 (8dcc466)

Compatibility Check #1: Rust 1.56.1
[OK] Is compatible

info: running cargo msrv verify -- cargo check --all-features on pack-release (7/8)
[Meta] cargo-msrv 0.15.1 (8dcc466)

Compatibility Check #1: Rust 1.59.0
[OK] Is compatible

info: running cargo msrv verify -- cargo check --all-features on sic (8/8)
[Meta] cargo-msrv 0.15.1 (8dcc466)

Compatibility Check #1: Rust 1.56.1
[OK] Is compatible