Fix check_mode for some _info modules. (#183)

plugins/modules/docker_stack_info.py

@@ -55,7 +55,7 @@ def main():
     module = AnsibleModule(
         argument_spec={
         },
-        supports_check_mode=False
+        supports_check_mode=True
     )
 
     rc, out, err = docker_stack_list(module)

plugins/modules/docker_stack_task_info.py

@@ -64,7 +64,7 @@ def main():
         argument_spec={
             'name': dict(type='str', required=True)
         },
-        supports_check_mode=False
+        supports_check_mode=True
     )
 
     name = module.params['name']