Can't use Symbol Overrides as placeholders
When trying to create re-usable symbols, the nested text layers values don't match the JSON fields. I'd assume you could place the placeholder variable name (that matches the JSON) into the Symbol override, but that doesn't seem to work. It actually replaces the override with the string value of the text layer, which overwrites the placeholder.

I've attached an example. Thanks.

[Archive.zip](https://github.com/preciousforever/sketch-data-populator/files/338347/Archive.zip)
