Do we need to restart the Nginx in a docker container?

I’ve the following Dockerfile:

FROM nginx
ARG BuildMode
ENV BuildMode=${BuildMode}
RUN echo BuildMode
COPY ./dist/omg-portal-frontend /usr/share/nginx/html
COPY ./nginx/default.${BuildMode}conf /etc/nginx/conf.d/default.conf

So do I need to add the following command? (to restart the Nginx service)

RUN service nginx restart

When I do, I get the following error:

[emerg] host not found in upstream "ppd-omg-backend-service.azure.omgcom.net" in /etc/nginx/conf.d/default.conf:17

Line 17:

proxy_pass http://ppd-omg-backend-service.azure.omgcom.net/;

Can anyone help me with this?
When I remove the command, I get build success, but I’m not sure if the container is reflecting the latest config changes…