Fix missing data source id in update (#5115)

This commit fixes a bug where the data source ID was not returned
when updating it via the service.

Signed-off-by: Adolfo García Veytia (Puerco) <puerco@stacklok.com>

internal/datasources/service/service.go

@@ -303,6 +303,10 @@ func (d *dataSourceService) Update(
 		return nil, fmt.Errorf("failed to commit transaction: %w", err)
 	}
 
+	if ds.Id == "" {
+		ds.Id = existing.ID.String()
+	}
+
 	return ds, nil
 }