docs: update unocss watch file path

[bowen-wu]

更新 unocss 文档问题
详见 issue: #9994

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Updated
umi	✅ Ready (Inspect)	Visit Preview	Dec 9, 2022 at 11:54AM (UTC)

[codecov]

Codecov Report

Base: 30.36% // Head: 30.36% // Decreases project coverage by -0.00% ⚠️

Coverage data is based on head (353220b) compared to base (c70a8c9).
Patch has no changes to coverable lines.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #10006      +/-   ##
==========================================
- Coverage   30.36%   30.36%   -0.01%     
==========================================
  Files         432      432              
  Lines       12332    12333       +1     
  Branches     2945     2946       +1     
==========================================
  Hits         3745     3745              
  Misses       8027     8027              
- Partials      560      561       +1     

Impacted Files	Coverage Δ
...ackages/preset-umi/src/commands/generators/jest.ts	0.00% <0.00%> (ø)
...ackages/preset-umi/src/features/webpack/webpack.ts	0.00% <0.00%> (ø)

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

☔ View full report at Codecov.
📢 Do you have feedback about the report comment? Let us know in this issue.