fix(python): required aggregator parameter in browse_* (#4016)

Author: shortcuts

templates/python/search_helpers.mustache

@@ -121,7 +121,7 @@
     {{^isSyncClient}}async {{/isSyncClient}}def browse_objects(
         self,
         index_name: str,
-        aggregator: Optional[Callable[[BrowseResponse], None]],
+        aggregator: Callable[[BrowseResponse], None],
         browse_params: BrowseParamsObject = BrowseParamsObject(),
         request_options: Optional[Union[dict, RequestOptions]] = None,
     ) -> BrowseResponse:
@@ -146,7 +146,7 @@
     {{^isSyncClient}}async {{/isSyncClient}}def browse_rules(
         self,
         index_name: str,
-        aggregator: Optional[Callable[[SearchRulesResponse], None]],
+        aggregator: Callable[[SearchRulesResponse], None],
         search_rules_params: SearchRulesParams = SearchRulesParams(hits_per_page=1000),
         request_options: Optional[Union[dict, RequestOptions]] = None,
     ) -> SearchRulesResponse: