CI: add templated Dockerfiles to build logs

Change-Id: I702f8fba37e22a6bb45eae14f1fbb251bcdb4d8a

.zuul.d/base.yaml

@@ -89,6 +89,7 @@
     extra-vars:
       kolla_logs_dir: "{{ zuul_output_dir }}/logs/kolla"
       kolla_build_logs_dir: "{{ kolla_logs_dir }}/build"
+      kolla_work_dir: "{{ kolla_logs_dir }}"
       virtualenv_path: "/tmp/kolla-virtualenv"
 
 - job:

tests/playbooks/run.yml

@@ -14,6 +14,7 @@
         # NOTE(yoctozepto): to avoid issues with IPv6 not enabled in the docker daemon
         # and since we don't need isolated networks here, use host networking
         network_mode: host
+        work_dir: "{{ kolla_work_dir }}"
   tasks:
     - name: Ensure /etc/kolla exists
       file: