Default count to 1 for backwards support

using count 1 ensures that the new system naturally outputs the same as the old system for old months (since all messages then just count 1, as they did before)

Author: Zabuzard

application/src/main/resources/db/V10__Alter_Top_Helper_Message_Length.sql

@@ -1 +1 @@
-ALTER TABLE help_channel_messages ADD message_length BIGINT DEFAULT 0 NOT NULL;
+ALTER TABLE help_channel_messages ADD message_length BIGINT DEFAULT 1 NOT NULL;