Make facet path of facets component optional

org.onehippo.cms7.essentials.components.info.EssentialsFacetsComponentInfo

This Info class has one parameter, but required. The EssentialsFacetsComponent though, can also work with the relative content path from the sitemap item. That makes the required = true here a bit strange.

Please remove the required = true, and update the label to for example something like "Facet Path (otherwise path from the sitemap item is used)".