Don't set user to nobody in runner

Author: jdav-dev

Dockerfile

@@ -112,6 +112,4 @@ ENV MIX_ENV="prod"
 # Only copy the final release from the build stage
 COPY --from=builder --chown=nobody:root /app/_build/${MIX_ENV}/rel/archivist ./
 
-USER nobody
-
 CMD ["/app/bin/archivist", "start"]