Only build one awx image instead of separate web and task images

installer/roles/local_docker/templates/docker-compose.yml.j2

@@ -3,7 +3,7 @@ version: '2'
 services:
 
   web:
-    image: {{ awx_web_docker_actual_image }}
+    image: {{ awx_docker_actual_image }}
     container_name: awx_web
     depends_on:
       - redis
@@ -72,7 +72,7 @@ services:
       no_proxy: {{ no_proxy | default('') }}
 
   task:
-    image: {{ awx_task_docker_actual_image }}
+    image: {{ awx_docker_actual_image }}
     container_name: awx_task
     depends_on:
       - redis
@@ -81,6 +81,7 @@ services:
       {% if pg_hostname is not defined %}
       - postgres
       {% endif %}
+    command: /usr/bin/launch_awx_task.sh
     hostname: {{ awx_task_hostname }}
     user: root
     restart: unless-stopped