Docker : "/sbin/tini" not found...

Hi, first of all, thanks for your work!

I trying to get the gateway running with docker and followed the documentation. At step "register" via:

docker run --rm -it -v signal-web-gateway_config:/signal/.config -v signal-web-gateway_storage:/signal/.storage registry.gitlab.com/morph027/signal-web-gateway:master register

I got the error:

docker: Error response from daemon: OCI runtime create failed: container_linux.go:367: starting container process caused: exec: "/sbin/tini": stat /sbin/tini: no such file or directory: unknown.

Any way to workaround or fix this ?

Another error so far is that master tag of image is not available like descried in documentation. To workaround that i changed tag to "latest".

Thanks in advanced!

Micha