Remove routing deprecations

[VigiePirate]

Router::prefix() is deprecated since Cakephp 4.3. : https://book.cakephp.org/4.next/en/appendices/4-3-migration-guide.html

Replaced by a call to the non-static method RouteBuilder::prefix().

[dereuromark]

You would need to also change min https://github.com/dereuromark/cakephp-geo/blob/master/composer.json#L23

[dereuromark]

Already solved in master afaik