fix(Service): await onPluginReady events to avoid concurrent issue

[kuitos]

Checklist

• npm test passes
• tests are included
• documentation is changed or added
• commit message follows commit guidelines

Description of change

onPluginReady event 没有 await 处理，可能导致 onPluginReady 里的变更因为时序问题而被忽略（比如在 onPluginReady 通过环境变量启用了另一个插件，另一个插件的 modifyDefaultConfig就会失效）

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This change is 

[codecov]

Codecov Report

Merging #5139 into master will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #5139   +/-   ##
=======================================
  Coverage   83.04%   83.04%           
=======================================
  Files         153      153           
  Lines        3385     3385           
  Branches      908      904    -4     
=======================================
  Hits         2811     2811           
  Misses        566      566           
  Partials        8        8           

Impacted Files	Coverage Δ
packages/core/src/Service/Service.ts	96.27% <100.00%> (ø)

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