Fix get_table_comment return value (#135)

Signed-off-by: Andras Sore <sore.andras@kodinformatika.hu>

Author: andrasore-kodinfo

ibm_db_sa/reflection.py

@@ -238,8 +238,7 @@ def get_table_comment(self, connection, table_name, schema=None, **kw):
             where(systbl.c.type == 'T').\
             where(systbl.c.tabschema == current_schema).\
             where(systbl.c.tabname == table_name)
-        c = connection.execute(query)
-        return {'text': c.first()}
+        return {'text': connection.execute(query).scalar()}
 
     @reflection.cache
     def get_view_names(self, connection, schema=None, **kw):