develop: add playground gitpod

[shczhen]

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[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• qiancai

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[winkyao]

LGTM

[qiancai]

/remove-status LGT1
/status LGT2

[qiancai]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: a876785