add `object` typeguard to `isObject` method (#2631)
add `object` typeguard to `isObject` method (#2631)


vega/vega-lite,uwdata/vega-lite,vega/vega-lite,vega/vega-lite,vega/vega-lite,uwdata/vega-lite,uwdata/vega-lite,uwdata/vega-lite,uwdata/vega-lite,vega/vega-lite