* Update `babel-plugin-transform-object-rest-spread` to v6.19.0

The `babel-plugin-transform-object-rest-spread` v6.19.0 update will
allow us to remove the `babel-plugin-transform-es2015-destructuring` and
`babel-plugin-transform-es2015-parameters` as the object rest spread
transform will now work standalone and not require additional tranforms

* Remove unnecessary babel transform plugins from babel-preset-react-app

The `babel-plugin-transform-object-rest-spread` v6.19.0 update makes
these plugins unnecessary, as v6.19.0 can be used stand-alone