Section rename handling in config/settings_data.json

[charlespwd]

Describe the bug
Looks like there's an undocumented behaviour of config/settings_data.json we'd need to think about:
https://github.com/Shopify/dawn/blob/main/config/settings_data.json#L173-L185

• Section type should be renamed
• Does that thing accept blocks? Do we rename blocks in there too?