fix: rework geocoding api usage, make api url custom

src/fellchensammlung/models.py

@@ -64,10 +64,9 @@ class Species(models.Model):
 
 class Location(models.Model):
     def __str__(self):
-        return f"{self.name}"
+        return f"{self.name} ({self.latitude:.5}, {self.longitude:.5})"
 
     place_id = models.IntegerField()
-    osm_id = models.IntegerField()
     latitude = models.FloatField()
     longitude = models.FloatField()
     name = models.CharField(max_length=2000)