configure TERR/Python/R services to use proxy to build docker image

Please allow to configure TERR/Python/R services to use proxy to build docker image.

The server needs to use proxy to connect to the internet and currently TERR service doesn't support to configure proxy to build docker images, also, TERR service can not utilize the proxy specified to docker on os level.

I tried to set "https_proxy" environment variable to start-terr-service.sh or pass "-Dhttps.proxyHost" property to java , but none of them works. Also I added proxy settings to docker on os level and I can run "docker pull ..." or "docker build ..." successfully but TERR services seems not able to recognize the proxy settings.

We know that prebuilding the docker image manually can workaround this, but the ability to use proxy setting would make it much more simpler.