Add Mastodon to Community website

[benjaoming]

Quick change proposal:

I'm not sure what version of Font Awesome we are running, and I didn't take time to setup a development environment yet.

This change will mark our website as "Verified" in our Mastodon profile because of the rel=me attribute. See: https://docs.joinmastodon.org/user/profile/#verification

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:books: Documentation preview :books:: https://read-the-docs-site-community--175.com.readthedocs.build/en/175/

[benjaoming]

Seems to work :+1:

[benjaoming]

@humitos if you re-save the profile https://fosstodon.org/@readthedocs, it should display the website as verified.

[benjaoming]

@humitos works now :100: