set_target fails even the target already exists

[j0eun]

Describe the bug
rast-cli only updates the list of sessions when run targets command.
Therefore set_target fails even rast-c2 has already the session.

To Reproduce
Run the set_target before running the targets.

Expected behavior
Connect to the session successfully.

[j0eun]

It can updates the list when running set_target, but I don't know it's a good way.
Because it needs to communicate with the C2 every target selection.