fix(error): Be consistent with rustc diagnostic guidelines

[epage]

From
https://rustc-dev-guide.rust-lang.org/diagnostics.html#suggestion-style-guide

Suggestions should not be a question. In particular, language like
"did you mean" should be avoided. Sometimes, it's unclear why a
particular suggestion is being made. In these cases, it's better to be
upfront about what the suggestion is.

The message may contain further instruction such as "to do xyz, use"
or "to do xyz, use abc".

Inspired by #2766

[epage]

It could probably use some more work and I'm hesitant in doing a change like this in a patch release as people might design some of their own CLI to match clap and changing it could provide a degraded experience, so we might want to call attention to this by saving it for a minor release.