Added `geoLocation` field to the `Channel` GraphQL type

• [GraphQL API] Added the following types to the GraphQL schema: Geometry, Point.
• [GraphQL API] Changed the Channel type:
  • Added the geoLocation field to the Channel type.

Introduced the following changes to the GraphQL schema (in SDL format):

extend type Channel {
  geoLocation: Geometry
}

interface Geometry {
  type: String!
}

type Point implements Geometry {
  coordinates: [Float!]!
  type: String!
}