Add support check mode for all info modules

As it's required by new ansible-test rules.
See https://github.com/ansible-collections/overview/issues/45#issuecomment-893543025
Change-Id: Ib6b73e810b972997b8de2b4a9eb8e07e246823d5

plugins/modules/server_info.py

@@ -70,6 +70,9 @@ class ServerInfoModule(OpenStackModule):
         filters=dict(required=False, type='dict', default=None),
         all_projects=dict(required=False, type='bool', default=False),
     )
+    module_kwargs = dict(
+        supports_check_mode=True
+    )
 
     def run(self):