Do not add read only attr in templates (#6010)

Author: gmazoyer

backend/infrahub/core/schema/schema_branch.py

@@ -1934,7 +1934,7 @@ def generate_object_template_from_node(
         # Tell if the user explicitely requested this template
         is_autogenerated_subtemplate = node.generate_template is False
         for node_attr in node.attributes:
-            if node_attr.unique:
+            if node_attr.unique or node_attr.read_only:
                 continue
 
             attr = AttributeSchema(

backend/tests/unit/core/schema_manager/test_manager_schema.py

@@ -2910,7 +2910,7 @@ async def test_manage_object_templates(relationship_kind: RelationshipKind):
     test_object_template_thing = schema_branch.get_template(f"Template{TestKind.THING}", duplicate=False)
     assert sorted(
         [a.name for a in test_object_template_thing.attributes if a.name != OBJECT_TEMPLATE_NAME_ATTR]
-    ) == sorted([a.name for a in THING_WITH_TEMPLATE.attributes if not a.unique])
+    ) == sorted([a.name for a in THING_WITH_TEMPLATE.attributes if not a.unique and not a.read_only])
     assert sorted(
         [
             r.name