Getting weird errors in CI related to apt update on the Cashtab server that are not coming from the ecash-lib build server.

Removing these steps does not impact the build in local testing.

docker build -f cashtab.Dockerfile -t cashtab_local . successful build

Change line 81 from ARG NGINX_CONF=nginx.conf to ARG NGINX_CONF=nginx-preview.conf

docker build -f cashtab.Dockerfile -t cashtab_local .
docker run --rm -p 8080:80 --name cashtab cashtab_local

navigate to localhost:8080 and Cashtab works, send some txs