Is loading bug

There is small bug in the search results section.

Update the following line of code to check metadata && !isLoading, currently we get: "loading earthquakes... 40 of 40 earthquakes in map area". Both of the conditions hit when auto load kicks off. https://code.usgs.gov/ghsc/hazdev/earthquake-latest-earthquakes/blob/master/projects/earthquake-latest-earthquakes/src/app/components/search-results/search-results.component.html#L19