Link in Readme to paid hosting is broken.

[Shy]

Hey folks,

This link is broken. Didn't want to just delete the line via a PR in case y'all have plans for swapping it out. For the record my org would love to chat with you about this option.

[steven-tey]

Not sure if it's the right link (found it via https://www.forem.com/self-host), but I took a stab at fixing the broken link in #94 :)

[Rafi993]

The link seems broken and I checked few places online and I couldn't find any reference. Did Forem stop providing paid hosting options?