NewGeoBoundingBoxQuery should support Geohash input

[tommed]

Please use the following questions as a guideline to help me answer
your issue/question without further inquiry. Thank you.

Which version of Elastic are you using?

[X ] elastic.v7 (for Elasticsearch 7.x)

Please describe the expected behavior

In Elastic I can specify top_left and bottom_right as geohash strings,

"query": {
  "bool": {
    "filter": [
        {
          "geo_bounding_box": {
            "metaData.location-point": {
              "top_left": "gcp7tpc",
        "bottom_right": "gcp7tpc"
              }
          }
        }
    ]
  }
}

Please describe the actual behavior

But in this API, my only options are BottomRightFromGeoPoint and TopLeftFromGeoPoint which require lat/lng type GeoPoint. The inner types are float64 so this prevents this type of query.

Any steps to reproduce the behavior?

query = query.Filter(elastic.
  NewGeoBoundingBoxQuery("metaData.location-point").
  TopLeftFromGeoPoint("dr5r9ydj2y73").
  BottomRightFromGeoPoint("dr5r9ydj2y73")