fix(input-number): fixed calucation issue when step is set decimal

[cisolarix]

closes #1007

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[codecov]

Codecov Report

Merging #1024 (a373da3) into main (5e219eb) will increase coverage by 0.11%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #1024      +/-   ##
==========================================
+ Coverage   46.93%   47.04%   +0.11%     
==========================================
  Files         511      511              
  Lines       12588    12593       +5     
  Branches     3547     3548       +1     
==========================================
+ Hits         5908     5925      +17     
+ Misses       5658     5646      -12     
  Partials     1022     1022              

Impacted Files	Coverage Δ
src/input-number/src/InputNumber.tsx	59.78% <100.00%> (+7.26%)	⬆️
src/input/src/Input.tsx	46.55% <0.00%> (+0.32%)	⬆️

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[07akioni]

@cisolarix 看起来这个 bug 已经在其他 PR 修复了，你可以把测试用例合一下，代码应该就不用了