Codegen: fix bug where stub rewriting globbles too much code

misc/codegen/generators/qlgen.py

@@ -319,7 +319,7 @@ def _get_stub(cls: schema.Class, base_import: str, generated_import_prefix: str)
 _stub_qldoc_header = "// the following QLdoc is generated: if you need to edit it, do it in the schema file\n"
 
 _class_qldoc_re = re.compile(
-    rf"(?P<qldoc>(?:{re.escape(_stub_qldoc_header)})?/\*\*.*?\*/\s*|^\s*)class\s+(?P<class>\w+)",
+    rf"(?P<qldoc>(?:{re.escape(_stub_qldoc_header)})?/\*\*.*?\*/\s*|^\s*)(?:class\s+(?P<class>\w+))?",
     re.MULTILINE | re.DOTALL)