feat: added cache serializer for webpack@5

[alexander-akait]

This PR contains a:

• bugfix
• new feature
• code refactor
• test update
• typo fix
• metadata update

Motivation / Use-Case

improve webpack@5 caching and avoid warnings

Breaking Changes

No

Additional Info

No

[codecov]

Codecov Report

Merging #581 into master will increase coverage by 1.91%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #581      +/-   ##
==========================================
+ Coverage   89.24%   91.16%   +1.91%     
==========================================
  Files           9        9              
  Lines         502      543      +41     
  Branches      143      145       +2     
==========================================
+ Hits          448      495      +47     
+ Misses         50       44       -6     
  Partials        4        4              

Impacted Files	Coverage Δ
src/CssDependency.js	100.00% <100.00%> (ø)
src/CssModule.js	98.24% <100.00%> (+17.69%)	⬆️

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