default value should be null

[diegogarciar]

Hello, im receiving this error in my console,

Invalid prop: type check failed for prop "filter". Expected Function, got String with value "".. I thing the default should be null or an empty function.

v-mapbox-geocoder/src/GeocoderControl.js

Line 183 in c0e3eeb

default: '',

having also the same issue for:
localGeocoder
render