Migrate to anstream for colors

[konstin]

Followup to #742.

[charliermarsh]

I think anstream itself doesn't do colors, it does the println / writeable stream, and it integrates with styling crates like owo-colors.

[BurntSushi]

I would check to see what Cargo is using for colors these days.

[konstin]

anstream and color-print rust-lang/cargo#12751

[BurntSushi]

Looks like anstream and color-print?