HackInternetAIUpdate does not transition to proper exit states

[charliefoxtwo]

As there's still a lot to do for state machines, #875 didn't handle many AI state machine transitions when giving an order to a hacker that is hacking. However, as these sorts of orders probably aren't given to hackers that often, it may be easy for this missing behavior to go unnoticed for quite some time, so I'm filing this issue so we remember.

Behaviors that are covered:

• Stop

Behaviors that are sort of covered:

• Move (doesn't use the proper move state machine, but that's not implemented yet)
• Garrison (since garrison doesn't use a state machine currently)

Behaviors that are not covered:

• Attack Move (accessible when selected with another non-hacker unit)
• Defend
• ???