[Test] Add test cases for utils

[kozistr]

Problem (Why?)

Need test cases for utils

Solution (What/How?)

• has_overflow
• normalize_gradient
• clip_grad_norm
• unit_norm
• get_optimizer_parameters

Other changes (bug fixes, small refactors)

nope

Notes

nope

[codecov-commenter]

Codecov Report

Merging #49 (fa6d4b1) into main (2162e68) will increase coverage by 1.04%.
The diff coverage is 75.00%.

@@            Coverage Diff             @@
##             main      #49      +/-   ##
==========================================
+ Coverage   85.89%   86.93%   +1.04%     
==========================================
  Files          25       25              
  Lines        1737     1738       +1     
==========================================
+ Hits         1492     1511      +19     
+ Misses        245      227      -18     

Impacted Files	Coverage Δ
pytorch_optimizer/version.py	0.00% <0.00%> (ø)
pytorch_optimizer/utils.py	91.83% <100.00%> (+37.67%)	⬆️

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