fix: add test cancel command

[shetzel]

What does this PR do?

Adds a command to cancel an agent test evaluation
Adds a NUT so CI builds will pass.

What issues does this PR fix or reference?

@W-17110700@

[jshackell-sfdc]

@shetzel , I'll wait until the first set of agent commands are further along and sorta working (however we define that in the first phase!) and then do a sweep of the help, okay? I think it's better to do it all at once when we're fairly secure in how they're going to work.

[shetzel]

@shetzel , I'll wait until the first set of agent commands are further along and sorta working (however we define that in the first phase!) and then do a sweep of the help, okay? I think it's better to do it all at once when we're fairly secure in how they're going to work.

Yes I agree. It's too early to have meaningful reviews of these commands, help text, and error messages. Each command will have a separate implementation story where the commands work as intended.