fix: check mergePrecision should consider zero

[jameslahm]

Fix ant-design/ant-design#30045, should consider mergedPrecision equals zero.

[vercel]

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[codecov]

Codecov Report

Merging #314 (59bece5) into master (4c53ce9) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #314   +/-   ##
=======================================
  Coverage   97.25%   97.25%           
=======================================
  Files           8        8           
  Lines         401      401           
  Branches      108      108           
=======================================
  Hits          390      390           
  Misses         11       11           

Impacted Files	Coverage Δ
src/InputNumber.tsx	98.17% <100.00%> (ø)

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[zombieJ]

+ rc-input-number@7.0.5