chore: more friendly tips

[AshoneA]

当时间选择框比较短的时候加个title会有个更友好的交互，能看到选择到的时间。

[vercel]

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[codecov]

Codecov Report

Merging #29 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master     #29   +/-   ##
======================================
  Coverage    99.2%   99.2%           
======================================
  Files          39      39           
  Lines        1756    1756           
  Branches      533     533           
======================================
  Hits         1742    1742           
  Misses          9       9           
  Partials        5       5

Impacted Files	Coverage Δ
src/Picker.tsx	99.09% <ø> (ø)	⬆️

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[afc163]

LGTM