Replace `io-lifetimes` crate with libstd types

[SludgePhD]

These have been stable since Rust 1.63.0, so there shouldn't be a need to incur this dependency anymore

[Drakulix]

io-lifetimes just reexports the std-types on recent rust versions, thus not adding a single bit of compiled code to the executable. I'd rather not bump the MSRV unnecessarily right now.

I am sure some dependency or feature will force this crate to bump the required version past 1.63 anyhow at some point, at which I will drop the dependency / merge this PR.

Still, thanks for the cleanup PR!