playground: fallback to default version when componen specific version is empty

[xhebox]

What problem does this PR solve?

Close #2343 . Fallback to default version when componen specific version is empty

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Code changes

• Has exported function/method change
• Has exported variable/fields change
• Has interface methods change
• Has persistent data change

Side effects

• Possible performance regression
• Increased code complexity
• Breaking backward compatibility

Related changes

• Need to cherry-pick to the release branch
• Need to update the documentation

Release notes:

NONE

[codecov-commenter]

Codecov Report

Attention: 1 lines in your changes are missing coverage. Please review.

Comparison is base (5618124) 53.39% compared to head (95bb130) 53.38%.

❗ Current head 95bb130 differs from pull request most recent head 90147f3. Consider uploading reports for the commit 90147f3 to get more accurate results

Files	Patch %	Lines
components/playground/playground.go	83.33%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2344      +/-   ##
==========================================
- Coverage   53.39%   53.38%   -0.01%     
==========================================
  Files         328      328              
  Lines       34825    34828       +3     
==========================================
- Hits        18593    18592       -1     
- Misses      13973    13976       +3     
- Partials     2259     2260       +1     

Flag	Coverage Δ
playground	15.31% <83.33%> (+0.01%)	⬆️
tiup	33.56% <ø> (-0.05%)	⬇️
unittest	22.35% <0.00%> (+<0.01%)	⬆️

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[kaaaaaaang]

/lgtm

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-12-28 08:17:06.35516052 +0000 UTC m=+1726517.392387434: ☑️ agreed by kaaaaaaang.

[kaaaaaaang]

/approve

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: kaaaaaaang

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