Improve the messages log for report in the migration tasks.

Add correct counting number of successfully/in error/.... tasks
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Numer of completed tasks: 9

Completed successfuly:
0
Require user attention:
0
Failed:
0
Note:
There are some tasks with unknown result.
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Should be

----------------------------------
Numer of completed tasks: 9

Completed successfuly:
7
Require user attention:
2
Failed:
0
------------------------------------