Fix(InputItem): this.state.value undefined error

[zack24q]

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if isBugFix :

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This change is 

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@9df1930). Click here to learn what that means.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master    #3044   +/-   ##
=========================================
  Coverage          ?   60.16%           
=========================================
  Files             ?       92           
  Lines             ?     2249           
  Branches          ?      646           
=========================================
  Hits              ?     1353           
  Misses            ?      887           
  Partials          ?        9

Flag	Coverage Δ
#web	60.16% <100%> (?)

Impacted Files	Coverage Δ
components/input-item/index.tsx	61.42% <100%> (ø)

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[doxiaodong]