Typo in docs [4.0 beta]

[boxofrox]

https://github.com/Marwes/combine/blob/v4.0.0-beta.1/src/parser/mod.rs#L70

...needs to be at least one implementation of two parse_streams or one parse_lazy? I'm not sure what the third option should be, or if there are only two options.

[tari]

It looks like one of them appeared in 6ec094e, which removed parse_stream_consumed and replaced the reference in the Parser documentation with parse_stream. Seems like there are only two options.