fix: determine webpack peer dependency version

[Knagis]

This PR contains a:

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

Motivation / Use-Case

Fixes #295

Breaking Changes

Additional Info

[jsf-clabot]

All committers have signed the CLA.

[codecov]

Codecov Report

Merging #296 into master will decrease coverage by 0.32%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #296      +/-   ##
==========================================
- Coverage   76.35%   76.02%   -0.33%     
==========================================
  Files           6        6              
  Lines         148      146       -2     
  Branches       52       51       -1     
==========================================
- Hits          113      111       -2     
  Misses         30       30              
  Partials        5        5              

Impacted Files	Coverage Δ
src/index.js	95.00% <100.00%> (-0.24%)	⬇️

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[alexander-akait]

We can merge it, but I am afraid you will get this problems with other plugins/loaders too, because many of them use const webpack = require('webpack')

[Knagis]

We can merge it, but I am afraid you will get this problems with other plugins/loaders too, because many of them use const webpack = require('webpack')

require("webpack") is completely fine - it picks up the peer dependency, so I can control which version which loader picks up.

the problem here is require('webpack/lib/web/FetchCompileWasmPlugin'). nodejs does not find the file in webpack 4 folder and thus walks up the directory chain and searches elsewhere.

in fact, without this change in the hoisted scenario parts like ExternalsPlugin is loaded from webpack 4, but FetchCompileWasmPlugin gets loaded from webpack 5

[alexander-akait]

Let's merge