fix typo in comment

[skip ci]

Author: apdavison

build.py

@@ -42,7 +42,7 @@
         for schema_identifier in conflicts:
             linked.remove(schema_identifier)
 
-    # Step 3b - translate and build each openMINDS schema as JSON-Schema
+    # Step 3b - translate and build each openMINDS schema as a Python class
     for schema_file_path in schemas_file_paths:
         module_path, class_name = PythonBuilder(
             schema_file_path, schema_loader.schemas_sources