MINOR: log add for pbi-bq lineage (#26211) (#26217)

Author: harshsoni2024

ingestion/src/metadata/ingestion/source/dashboard/powerbi/metadata.py

@@ -1012,7 +1012,10 @@ def _parse_redshift_source(self, source_expression: str) -> Optional[List[dict]]
         return None
 
     def _parse_bigquery_source(
-        self, source_expression: str, datamodel_entity: DashboardDataModel
+        self,
+        source_expression: str,
+        datamodel_entity: DashboardDataModel,
+        table: PowerBiTable,
     ) -> Optional[List[dict]]:
         """
         Parse BigQuery source from Power Query M expressions.
@@ -1049,15 +1052,14 @@ def _parse_bigquery_source(
                             )
                             # Recursively parse the referenced expression
                             return self._parse_bigquery_source(
-                                dexpression.expression, datamodel_entity
+                                dexpression.expression, datamodel_entity, table
                             )
 
             # Check if this is a direct BigQuery connection
             if "GoogleBigQuery.Database" not in source_expression:
                 return None
 
             logger.debug(f"Found GoogleBigQuery.Database in expression")
-
             # Extract project, dataset (schema), and table from BigQuery M expression
             # Pattern: [Name="project"][Data][Name="dataset",Kind="Schema"][Data][Name="table",Kind="Table"]
 
@@ -1087,7 +1089,10 @@ def _parse_bigquery_source(
             logger.debug(
                 f"Extracted BigQuery info: project={project}, dataset={dataset}, table={table_name}"
             )
-
+            if not table_name:
+                logger.debug(
+                    f"Parsing BigQuery source expression for powerbi table ({table.name}):: {source_expression}"
+                )
             if table_name:
                 return [{"database": project, "schema": dataset, "table": table_name}]
 
@@ -1345,7 +1350,7 @@ def _parse_table_info_from_source_exp(
 
             # parse bigquery source
             table_info_list = self._parse_bigquery_source(
-                source_expression, datamodel_entity
+                source_expression, datamodel_entity, table
             )
             if isinstance(table_info_list, List):
                 return table_info_list