Fix regression in naturalsize for float and str

[loicleyendecker]

Currently if gnu is set to False, calling naturalsize(1.0) or naturalsize("1") will return "1.0 Byte instead of "1 Byte", which was the return value until 4.12.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.49%. Comparing base (8059ebe) to head (a79fb3a).
Report is 11 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #250   +/-   ##
=======================================
  Coverage   99.49%   99.49%           
=======================================
  Files          11       11           
  Lines         798      798           
=======================================
  Hits          794      794           
  Misses          4        4           

Flag	Coverage Δ
macos-latest	97.74% <100.00%> (ø)
ubuntu-latest	97.74% <100.00%> (ø)
windows-latest	95.73% <100.00%> (ø)

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[hugovk]

Thanks for the fix.

Like #239, this was also caused by #226 and this is the similar fix for the other case.

[hugovk]

Thanks!