fix some typos

src/nominatim_api/search/db_search_builder.py

@@ -275,7 +275,7 @@ class SearchBuilder:
                               use_lookup: bool) -> List[dbf.FieldLookup]:
         """ Create a ranking expression with full name terms and
             additional address lookup. When 'use_lookup' is true, then
-            address lookups will use the index, when the occurences are not
+            address lookups will use the index, when the occurrences are not
             too many.
         """
         # At this point drop unindexed partials from the address.

src/nominatim_db/tools/refresh.py

@@ -154,7 +154,7 @@ def import_importance_csv(dsn: str, data_file: Path) -> int:
     if not data_file.exists():
         return 1
 
-    # Only import the first occurance of a wikidata ID.
+    # Only import the first occurence of a wikidata ID.
     # This keeps indexes and table small.
     wd_done = set()