Sphinx config should not store custom class instances #289
Description
No custom classes should be stored to the configuration.
Same reasoning as in #288.
WARNING: Unsupported type at 'needs.render_context.draw_interface': draw_full_interface - filtering out [needs_config_writer.unsupported_type]
WARNING: Unsupported type at 'needs.render_context.draw_module': draw_full_module - filtering out [needs_config_writer.unsupported_type]
WARNING: Unsupported type at 'needs.render_context.draw_component': draw_full_component - filtering out [needs_config_writer.unsupported_type]
WARNING: Unsupported type at 'needs.render_context.draw_feature': draw_full_feature - filtering out [needs_config_writer.unsupported_type]