A few fix of the daemon_manager

* Adjust the default process termination timeout to give some more time
  when waiting process to terminate.
* Remove the try...catch block for getting memory and cpu useage as the
  exception will be caught by the caller anyway.

Test: atest daemon_manager_test
Bug: 365617369
Change-Id: I91db1cd65045dccc9eaf3cf8ceacbbf5eaf85298