fix(Nav): make Nav can be collapsed after clicked item

[Kimi-Gao]

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[codecov]

Codecov Report

Merging #271 into master will increase coverage by 0.05%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #271      +/-   ##
==========================================
+ Coverage   17.81%   17.86%   +0.05%     
==========================================
  Files          71       71              
  Lines        1398     1399       +1     
  Branches      313      314       +1     
==========================================
+ Hits          249      250       +1     
  Misses        882      882              
  Partials      267      267              

Impacted Files	Coverage Δ
src/components/Nav/Nav.js	100.00% <100.00%> (ø)

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