Optimize bn.js package

[nenadV91]

Summary

Fixes #2449

This will make sure the bn.js package is included only once in production build instead of multiple times and reduce the size of the bundle

For reference https://stackoverflow.com/a/65119222/4620771

Before

After

To test

• you can run yarn build:analyze to start webpack bundle analyzer

[github-actions]

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[github-actions]

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[elena-zh]

hey @nenadV91 , I'm still testing, but here is the issue I have faced: when try to trade and get a native currency when connected to SC wallet (Safe), I get a different error in this pr:

Expected behavior:

[elena-zh]

It is appeared that the issue is not related to the Safe wallet: I get the same error when try to buy XDAI when connected to MM:

All the rest changes LGTM

[elena-zh]

@nenadV91 , I reported a separate issue for the comments above #2482 as the issue is not related to the current PR.

[alfetopito]

Whoa! Pure magic ✨