rust language: use the new cargo install command

[zimbatm]

cargo install now requires an additional --path <TARGET> argument.

Fixes #1112

[asottile]

[asottile]

E error: /tmp/pytest-of-vsts/pytest-0/test_rust_hook0/0/.pre-commit/repoy25Xd6/rustenv-default is not a directory. --path must point to a directory containing a Cargo.toml file.

hmm ok after reading the docs it seems that --path should be used when installing . essentially (and not needed otherwise) -- so I think --path . is what we want here?

[zimbatm]

I'm not sure which path is which. Let's see what the CI has to say.

[asottile]

well now I have no idea, maybe @chriskuehl knows better?

E               error: could not find `shellharden` in /tmp/pytest-of-vsts/pytest-0/test_additional_rust_cli_depen0/0/.pre-commit/repopsLO1P with version `=3.1.0`