Fix unit test timeout

[GuoLei1990]

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• Tests for the changes have been added (for bug fixes / features)
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[codecov]

Codecov Report

Patch coverage: 50.00% and project coverage change: +0.12% 🎉

Comparison is base (40f6ab4) 62.17% compared to head (f71e6bf) 62.29%.
Report is 8 commits behind head on dev/1.1.

❗ Current head f71e6bf differs from pull request most recent head 5b51a13. Consider uploading reports for the commit 5b51a13 to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##           dev/1.1    #1733      +/-   ##
===========================================
+ Coverage    62.17%   62.29%   +0.12%     
===========================================
  Files          430      430              
  Lines        22542    22545       +3     
  Branches      3202     3203       +1     
===========================================
+ Hits         14015    14045      +30     
+ Misses        7300     7280      -20     
+ Partials      1227     1220       -7     

Files Changed	Coverage Δ
packages/loader/src/SceneLoader.ts	6.77% <0.00%> (-0.37%)	⬇️
packages/core/src/mesh/SkinnedMeshRenderer.ts	61.87% <71.42%> (+6.87%)	⬆️

... and 5 files with indirect coverage changes

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