fix: 在picker组件中使用calendar组件时, calendar的selectValue属性无效问题

[Crayonn]

问题描述：
picker组件的会拦截calendar的selectValue， 这个是有什么考虑吗？

const calendar = (
            <Calendar selectValue={moment()}/>  // 此时calendar组件中的selectValue 为 undefined
        )
        return (
            <Picker calendar={calendar}>
                {this.renderChild}
            </Picker>
        );

[codecov]

Codecov Report

Merging #615 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #615   +/-   ##
=======================================
  Coverage   90.78%   90.78%           
=======================================
  Files          10       10           
  Lines         716      716           
  Branches      214      214           
=======================================
  Hits          650      650           
  Misses         57       57           
  Partials        9        9

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