Use network=host on docker buildx build

We are already creating a custom buildx builder with options set to use
host networking. However, there are reports that this isn't sufficient
to get builds working in all situations. It is reported that adding
--network=host to the build command itself does fix things. Considering
we already intend to use host networking (per the custom buildx builder
options) lets go ahead and set --network=host on build commands as well.

This upstream issue may be related:
  https://github.com/docker/buildx/issues/1688
to the problems that have been observed, but it doesn't seem to match
completely. Maybe upstream behaviors changed since this was origianlly
reported?

Change-Id: Ie8856cf49b86e89e2bc903033e7a20874b7c9f83

roles/build-container-image/tasks/buildx.yaml

@@ -19,6 +19,7 @@
     docker_buildx_command: >-
       docker buildx build {{ zj_image.path | default('.') }}
       {% if containerfile %}-f {{ containerfile }}{% endif %}
+      --network=host
       {% if zj_image.target | default(false) -%}
         --target {{ zj_image.target }}
       {% endif -%}

roles/build-docker-image/tasks/buildx.yaml

@@ -8,6 +8,7 @@
   set_fact:
     docker_buildx_command: >-
       docker buildx build {{ zj_image.path | default('.') }} -f {{ zj_image.dockerfile | default(docker_dockerfile) }}
+      --network=host
       {% if zj_image.target | default(false) -%}
         --target {{ zj_image.target }}
       {% endif -%}

roles/upload-docker-image/tasks/buildx.yaml

@@ -10,6 +10,7 @@
   # should result in a noop build and just a push.
   command: >-
     docker buildx build {{ zj_image.path | default('.') }} -f {{ zj_image.dockerfile | default(docker_dockerfile) }}
+    --network=host
     {% if zj_image.target | default(false) -%}
       --target {{ zj_image.target }}
     {% endif -%}