update syntax to remove DEPRECATION WARNINGs

roles/build_docker_images/tasks/build_standalone.yml

@@ -32,9 +32,11 @@
   docker_image:
     name: "{{repo}}/{{item}}"
     tag: "{{version}}{{suffix}}"
-    path: "{{docker_build_dir}}/{{item}}"
-    dockerfile: "{{docker_build_dir}}/{{item}}/Dockerfile"
-    pull: no
+    build:
+      path: "{{docker_build_dir}}/{{item}}"
+      dockerfile: "{{docker_build_dir}}/{{item}}/Dockerfile"
+      pull: no
     source: build
     state: present
   with_items: "{{services}}"
+