Wemake-python-styleguide: Add flake8-spellcheck to docs

[sobolevn]

Let's add this awesome plugin to the list of external plugin in the docs!
Docs: https://github.com/wemake-services/wemake-python-styleguide/blob/master/docs/pages/usage/integrations/plugins.rst

Link: https://github.com/MichaelAquilina/flake8-spellcheck

[charleshayes]

@sobolevn May I take over this issue? I am looking to make my first open source contribution, and this would be a great entry point for me.

[sobolevn]

@charleshayes absolutely! Thanks a lot!

[sobolevn]

@charleshayes friendly ping 🙂 Do you need any help from my side?

Just to be helpful: you can use github website to do this task, no need to fork / clone it manually. See https://help.github.com/en/github/managing-files-in-a-repository/editing-files-in-your-repository

[sobolevn]

@charleshayes feel free to send a PR in any case, but I will leave this issue for some other new-comer 🙂

[leksuss]

Hello, let me take it :)

[sobolevn]

@leksuss thanks!

[leksuss]

@sobolevn should I add so minor changes to the CHANGELOG.md ?

[sobolevn]

No, this is not required 🙂