Update owncast to 0.0.12

From: CTS - FreeBSD Team <de-freebsd_at_ctseuro.com>
Date: Tue, 09 Aug 2022 17:26:56 UTC
I just submitted bug #265744 that is supposed to update owncast to 

I tested it with go-1.18 and it works for me.


Please have a closer look before commiting as i am not the most 
expirienced maintainer out there.

Markus Mann, CTS - FreeBSD Team
WWW: https://cts-solutions.at/