Ensure actor_id gets passed in case channel creation API endpoint ends up in undeleting channel

[rtibbles]

Summary

Description of the change(s) you made

When trying to chef a previously deleted channel, the API endpoint would return a 500 because the actor_id argument was not being passed to the save method.
This is required, as the channel would be undeleted by this operation, so this is needed for the channel history tracking.

Manual verification steps performed

1. Wrote a regression test, saw that it failed.
2. Fixed the issue.
3. Saw that it passed!

References

Fixes #4783

Comments

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[bjester]

Regression test LGTM