* Remove unneeded ESLint suppression

* Regenerate package-lock.json

* Enable and fix all occurrences with no-mixed-operators rule
* Take care of the max-depth warning in button.js

Signed-off-by: mhatvan <markus_hatvan@aon.at>

Notably:

* bundlesize 0.15.3 → ^0.17.2
* eslint-plugin-unicorn ^8.0.2 → ^9.0.0
* terser ^3.17.0 → ^4.0.0

Also, refactor ESLint and stylelint config files; now everything will work from our root dir.

We can check for browser compatibility on lint time now.

Ignore ESLint error in ie-emulation-modes-warning.js.

Although the error is valid, enough time has been spent on old IE's problems, so just ignore it.

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Fixes #19908

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Refs #19908

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Refs #19908.

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Refs #19908

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Refs http://eslint.org/docs/user-guide/migrating-to-2.0.0#new-rules-in-eslintrecommended

Refs http://eslint.org/docs/user-guide/migrating-to-2.0.0

Refs #19908

Refs #19908

Enable new rules:
* no-empty-pattern
* no-magic-numbers (exempting 0 and ±1)

Refs #19908

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That way, ESLint won't look in parent dirs for configuration files.