docker: Remove trailing whitespace.
docker: Remove trailing whitespace.

andersk/zulip,zulip/zulip,rht/zulip,rht/zulip,rht/zulip,rht/zulip,zulip/zulip,rht/zulip,rht/zulip,zulip/zulip,zulip/zulip,andersk/zulip,andersk/zulip,andersk/zulip,zulip/zulip,andersk/zulip,andersk/zulip,andersk/zulip,zulip/zulip,zulip/zulip,rht/zulip