Make all social icons same size (Mattermost icon is bigger at least visually )

[pavlenex]

Make all icons in Join The Community section the same size.

Tested on 13" screen.

Join The Community: For the Desktop viewport the copytext ("BTCPay Server is an open-source project, …") runs too wide. (give it a max-width: 42em; or something similar)

[vswee]

Better?

[pavlenex]

Looks good now @vswee! I'm kinda missing some hover indicator there, should we add that?

[vswee]

Added a bounce. Maybe colour is a step too far?

[pavlenex]

I don't mind colors but yellow GitHub logo triggers me, perhaps we can use their standard purple logo?

But could be that it's too much as we already have colors on integration page, your call.