Incompatibility with firebase-admin 11.5.0

[sentd94]

    GeoFireClient.prototype.point = function (latitude, longitude) {
        return {
            geopoint: new this.app.firestore.GeoPoint(latitude, longitude),
            geohash: encode(latitude, longitude, 9)
        };
    };

this.app.firestore.GeoPoint is not a constructor in the latest version.

This leads to an issue when trying to create a GeoPoint like this (when using the latest firebase-admin version):

const position = geo.point(40, -119);