the content of 'The stable version' should follow the actual release version when a user uses 'tiup playground'.

[lilyjazz]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. What did you do?

$ tiup playground

2. What did you expect to see?

Starting component `playground`: /root/.tiup/components/playground/v1.4.1/tiup-playground
Use the latest stable version: v5.0.0

    Specify version manually:   tiup playground <version>
    The stable version:         tiup playground v 4.0.0 
    The nightly version:        tiup playground nightly

The stable version is incorrect. 'v5.0.0' should be dispalyed.

3. What did you see instead?

Starting component `playground`: /root/.tiup/components/playground/v1.4.1/tiup-playground
Use the latest stable version: v5.0.0

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

the content of 'The stable version' should follow the actual release version.

4. What version of TiUP are you using (tiup --version)?

$ tiup --version
1.4.0 tiup
Go Version: go1.16.2
Git Ref: v1.4.0
GitHash: eb335e6ad9d0dc19d1c43db422cd409d62bc3cea

[AstroProfundis]

This is a prompted example to show user how to start playground with a specified version of TiDB. So the v4.0.0 part in it is hard coded and does not reflect any actual version used.

I'll try to update the message to make it less confusing.