fix(core): command option type bug

[NWYLZW]

#331

[codecov]

Codecov Report

Merging #332 (f7070b4) into develop (d41c9b7) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff            @@
##           develop     #332   +/-   ##
========================================
  Coverage    92.78%   92.78%           
========================================
  Files           57       57           
  Lines        11436    11436           
  Branches      2368     2368           
========================================
  Hits         10611    10611           
  Misses         825      825           

Impacted Files	Coverage Δ
packages/koishi-core/src/parser.ts	99.48% <100.00%> (ø)

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[shigma]

这个 PR 是不是可以修复 #331 的问题？

[NWYLZW]

这个 PR 是不是可以修复 #331 的问题？

y，是的，可以看我添加的两行单元测试