playground: fix cannot bind 0.0.0.0

[nexustar]

What problem does this PR solve?

Fix #1800

What is changed and how it works?

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

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• AstroProfundis

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[codecov-commenter]

Codecov Report

Merging #1811 (79bf49a) into master (cba67ca) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #1811   +/-   ##
=======================================
  Coverage   52.88%   52.88%           
=======================================
  Files         303      303           
  Lines       34789    34789           
=======================================
  Hits        18398    18398           
  Misses      14231    14231           
  Partials     2160     2160           

Flag	Coverage Δ
playground	12.63% <100.00%> (-0.01%)	⬇️
tiup	14.39% <ø> (ø)
unittest	21.29% <ø> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
components/playground/playground.go	48.89% <ø> (-0.12%)	⬇️
components/playground/instance/tiflash.go	59.12% <100.00%> (ø)
components/playground/instance/tiflash_config.go	72.22% <100.00%> (+1.63%)	⬆️
...onents/playground/instance/tiflash_proxy_config.go	80.00% <100.00%> (+1.43%)	⬆️

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[AstroProfundis]

/merge

[ti-chi-bot]

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

Commit hash: 79bf49a