add types for ts support and support webpack v5 config

[YanYuanFE]

This PR contains a:

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

Motivation / Use-Case

add types for ts support and support webpack v5 config

Breaking Changes

Additional Info

[codecov]

Codecov Report

Merging #594 (5ac0836) into master (bb09d75) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #594   +/-   ##
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  Coverage   91.16%   91.16%           
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  Files           9        9           
  Lines         543      543           
  Branches      145      145           
=======================================
  Hits          495      495           
  Misses         44       44           
  Partials        4        4           

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[alexander-akait]

Sorry, we should use ts docs to generate types, also it was implemented after webpack@5 stable release

[PodaruDragos]

@alexander-akait are there any plans to add types directly in this package and not rely on @types/mini-css-extract-plugin ?