fix(elasticsearch-ingestion): detect sub-properties in 'nested' type …

…mapping

fix issue where sub-properties in 'nested' type mappings are not detected during
Elasticsearch ingestion, resulting in incomplete ingestion of data. Prior to this
fix, only top-level properties were recognized, missing critical sub-fields.

Fixes: datahub-project#10911

metadata-ingestion/src/datahub/ingestion/source/elastic_search.py

@@ -138,7 +138,7 @@ def _get_schema_fields(
         for columnName, column in elastic_schema_dict.items():
             elastic_type: Optional[str] = column.get("type")
             nested_props: Optional[Dict[str, Any]] = column.get(PROPERTIES)
-            if elastic_type is not None:
+            if elastic_type is not None and elastic_type != "nested":
                 self._prefix_name_stack.append(f"[type={elastic_type}].{columnName}")
                 schema_field_data_type = self.get_column_type(elastic_type)
                 schema_field = SchemaField(