Clicking on "join us on Discord to collaborate!" doesn't work

[calumtomeny]

Clicking on "join us on Discord to collaborate!" on the ReadMe page takes me to an "Invite Invalid" page.

The expected behaviour is that I can join the discord server. Perhaps the link (https://discord.com/invite/zE8guNfG49) has expired?

[ckoopmann]

I opened a PR that should fix this:
#22