Update REST API for spatial information format in JSON-LD content

[lulin-song]

An iSamples user found a typo in JSON-LD content on the sample landing page. LS also found another bug in JSON-LD content. Single point was mistakenly repeated twice as multiple points.
After discussion, the following format of sample spatial information is agreed upon. Since it compliant with ESIP recommendation and Google schema.
https://github.com/ESIPFed/science-on-schema.org/blob/master/assets/diagrams/dataset/dataset_spatial-coverage.svg
https://schema.org/geo
The example format is below.
"geoLocation": {
              "@type": "Place",
"geo": [
{
                                   "@type": "GeoCoordinates",
                                   "latitude": "40.75",
                                   "longitude": "73.98"
}
]
        }