fix: empty children is a leaf node

[zombieJ]

resolve ant-design/ant-design#34062

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[codecov]

Codecov Report

Merging #250 (92ba529) into master (5361320) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #250   +/-   ##
=======================================
  Coverage   99.79%   99.79%           
=======================================
  Files          15       15           
  Lines         484      485    +1     
  Branches      122      123    +1     
=======================================
+ Hits          483      484    +1     
  Misses          1        1           

Impacted Files	Coverage Δ
src/hooks/useSearchOptions.ts	100.00% <100.00%> (ø)

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