Update config.md
Update config.md

JSON schema has strokeDashOffset as Number not Number[] (I assume the schema is current and the docs are wrong?)
uwdata/vega-lite,uwdata/vega-lite,uwdata/vega-lite,uwdata/vega-lite,vega/vega-lite,vega/vega-lite,vega/vega-lite,uwdata/vega-lite,vega/vega-lite,vega/vega-lite