bug: return correct err message

if the sql query failed has is false and the method will return
m.ErrDataSourceNotFound which is incorrect. We now return the
correct error message from the query

ref #10843

pkg/services/sqlstore/datasource.go

@@ -27,6 +27,9 @@ func GetDataSourceById(query *m.GetDataSourceByIdQuery) error {
 
 	datasource := m.DataSource{OrgId: query.OrgId, Id: query.Id}
 	has, err := x.Get(&datasource)
+	if err != nil {
+		return err
+	}
 
 	if !has {
 		return m.ErrDataSourceNotFound