start tiup playground with a previous nightly version

Feature Request

Command tiup playground nightly will start with the latest version while I hope to use a previous version.

the latest version: v5.0.0-nightly-20210624

target version: v5.0.0-nightly-20210617

try the following command: tiup playground v5.0.0-nightly-20210617

Output:

Found playground newer version:
    The latest version:         v1.5.2
    Local installed version:    v1.5.1
    Update current component:   tiup update playground
    Update all components:      tiup update --all
Starting component `playground`: /home/xzx/.tiup/components/playground/v1.5.1/tiup-playground v5.0.0-nightly-20210617
Error: Playground bootstrapping failed: no version on linux/amd64 for component tidb satisfies constraint "v5.0.0-nightly-20210617"
Error: run `/home/xzx/.tiup/components/playground/v1.5.1/tiup-playground` (wd:/home/xzx/.tiup/data/SbJESMy) failed: exit status 1

v5.0.0-nightly-20210617 files did exist in the local.

Hope we could start tiup playground with a previous nightly version

Reproduce the issue with tiup playground nightly and tiup playground v5.0.0-nightly-20210617, using the reported local component files. Trace the playground command's version selection and component constraint handling. Done means a previously available nightly version can start successfully instead of failing with a missing-version error.