update BaseFiltersClient

Author: vincentsarago

stac_fastapi/extensions/stac_fastapi/extensions/core/filter/client.py

@@ -49,7 +49,7 @@ def get_queryables(
         https://github.com/stac-api-extensions/filter#queryables
         """
         return {
-            "$schema": "https://json-schema.org/draft/2019-09/schema",
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
             "$id": "https://example.org/queryables",
             "type": "object",
             "title": "Queryables for Example STAC API",