fix: parse tsconfig.json error

[zhanba]

• tsconfig.json 不是严格的json, tsc --init生成的默认 tsconfig.josn 就带有很多注释。
  这里将JSON.parse 换成ts自带的api，保证兼容。
• 另外修复一个小的测试bug。

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@e54641b). Click here to learn what that means.
The diff coverage is 91.66%.

@@            Coverage Diff            @@
##             master     #157   +/-   ##
=========================================
  Coverage          ?   74.29%           
=========================================
  Files             ?       16           
  Lines             ?      459           
  Branches          ?      160           
=========================================
  Hits              ?      341           
  Misses            ?      117           
  Partials          ?        1

Impacted Files	Coverage Δ
packages/father-build/src/babel.ts	81.08% <91.66%> (ø)

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