service: Allow additional dependencies for additional containers

roles/service/meta/argument_specs.yaml

@@ -571,6 +571,23 @@ argument_specs:
                   the name of the environment variable. Defaults to secret name.
                 type: str
                 required: false
+          requires:
+            description: >-
+              List of systemd units this container depends on, in addition to
+              service-wide requires.
+            type: list
+            required: false
+            default: []
+            elements: str
+          wants:
+            description: >-
+              List of systemd units this container weakly depends on, in addition to
+              service-wide wants.
+            type: list
+            required: false
+            default: []
+            elements: str
+
 
       service_requires:
         description: List of systemd units this service container depends on.