add `cargo-features` to unstable docs for workspace inheritance
add `cargo-features` to unstable docs for workspace inheritance

rustyhorde/cargo,rust-lang/cargo,rustyhorde/cargo,nipunn1313/cargo,eminence/cargo,rustyhorde/cargo,rust-lang/cargo,nipunn1313/cargo,eminence/cargo,nipunn1313/cargo,eminence/cargo,rust-lang/cargo,rust-lang/cargo,rustyhorde/cargo,nipunn1313/cargo,eminence/cargo