Switch to Github Container Registry

Moves to Github Container Registry for builder
images.

Dockerfile-build

@@ -1,4 +1,4 @@
-FROM netbootxyz/docker-builder:latest as builder
+FROM ghcr.io/netbootxyz/docker-builder:latest as builder
 
 ENV DEBIAN_FRONTEND=noninteractive
 

Dockerfile-build.production

@@ -1,4 +1,4 @@
-FROM netbootxyz/docker-builder:latest as builder
+FROM ghcr.io/netbootxyz/docker-builder:latest as builder
 
 ENV DEBIAN_FRONTEND=noninteractive