chore: add ts-ignore for defineConfig.d.ts

[sorrycc]

Checklist

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

Description of change

• 为 defineConfig.d.ts 添加 ts-ignore，避免依赖 umi 时的 tsc 报错

[codecov]

Codecov Report

Merging #4613 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #4613   +/-   ##
=======================================
  Coverage   82.80%   82.80%           
=======================================
  Files         144      144           
  Lines        2908     2908           
  Branches      728      728           
=======================================
  Hits         2408     2408           
+ Misses        492      491    -1     
- Partials        8        9    +1     

Impacted Files	Coverage Δ
packages/core/src/Config/Config.ts	61.15% <0.00%> (ø)

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