fix dangling links in documentation

src/nominatim_api/core.py

@@ -382,7 +382,7 @@ class NominatimAPI:
 
     @property
     def config(self) -> Configuration:
-        """ Provide read-only access to the [configuration](#Configuration)
+        """ Provide read-only access to the [configuration](Configuration.md)
             used by the API.
         """
         return self._async_api.config

src/nominatim_api/results.py

@@ -127,7 +127,7 @@ class AddressLine:
 
     local_name: Optional[str] = None
     """ Place holder for localization of this address part. See
-        [Localization](#localization) below.
+        [Localization](Result-Handling.md#localization) below.
     """