version information message is confusing

[nrc]

I run tiup playground, there is some boilerplate on the console, and

Use the latest stable version: v4.0.7

    Specify version manually:   tiup playground <version>
    The stable version:         tiup playground v4.0.0
    The nightly version:        tiup playground nightly

This is in yellow, which suggests its a warning, but its not clear if something is wrong or not (I guess this is just information). It is not clear to me what this is telling me or why. I think the whole message could probably just be removed. If it is kept I recommend changing the colour and re-wording:

INFO currently using latest stable version: v4.0.7.
INFO to specify a version, use `tiup playground <version>`
INFO `<version>` can be a version number, e.g., `v4.0.0`, or a channel name: `stable` or `nightly`

[lonng]

@nrc Prefer to keep the information but change its color.