Update nominatim location example

[martinlagler]

Q	A
Related PRs	sulu/sulu#7172
License	MIT

What's in this PR?

Fix the example code for the geolocators.

Why?

Because the API changed.

[remdan]

This is not enough...
the locate function is based on: https://nominatim.org/release-docs/develop/api/Search/
but the new api is not compatible: https://developer.mapquest.com/documentation/geocoding-api/address/get/

currently would work:

sulu_location:
  geolocator: nominatim
  geolocators:
    nominatim:
      endpoint:             'https://nominatim.openstreetmap.org/search?'

[alexander-schranz]

@remdan thx for the hints do you have some background about the history of the api changes. Let move the discussion to the open pull request: https://github.com/sulu/sulu/pull/7172/files#r1410619521