There are various negative effects if these settings are allowed in the extra options for txt2img or img2img. This PR removes them from the extra_options lists at load time.
'sd_model_checkpoint' and 'CLIP_stop_at_last_layers' will invisibly override main UI settings, leading to confusing behaviour
'sd_vae' doesn't seem harmful, but can create an empty block in the UI section
'forge_additional_modules' causes an error that prevents the UI from loading