Support for MapArrays in Geozero data source

[kylebarron]

from @Bonkles

panicked at /Users/clarkben/working/OvertureMaps/geoarrow-rs/src/io/geozero/table/data_source.rs:349:19:
not yet implemented: unsupported type: Map(Field { name: "key_value", data_type: Struct([Field { name: "key", data_type: Utf8, nullable: false, dict_id: 0, dict_is_ordered: false, metadata: {} }, Field { name: "value", data_type: Utf8, nullable: true, dict_id: 0, dict_is_ordered: false, metadata: {} }]), nullable: false, dict_id: 0, dict_is_ordered: false, metadata: {} }, false)