Update fish completions to satisfy brew man

[Rylan12]

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Follow up to #10431. Between creation and merge some command descriptions were changed. I didn't do a final rebase so brew man is now failing. This PR is a quick fix to let CI pass.

[BrewTestBot]

Review period skipped due to critical label.

[BrewTestBot]

Review period skipped due to critical label.

[Rylan12]

Looks like tests are failing consistently here. Not sure why as they shouldn't be affected by this PR. Unfortunately, this PR is also blocking CI from passing on the master branch. I will continue to investigate but I'm not super optimistic as I can't seem to reproduce these errors locally.

Worst case, I can temporarily skip these tests to get passing CI. I'd rather not do this, though.

Edit: trying again because I can't think of anything else to do. I have no issues running this locally.

[Rylan12]

Okay, I'm at a loss. Any ideas or should I just go ahead and skip the test for now?

Edit: I tried increasing the timeout for this test. Let's see if this works before skipping.

Okay, now nothing's running. Maybe it's a GitHub actions issue? I'm going to take a break and I'll check back later to see how this is going.

[Rylan12]

Yep, looks like GitHub's the culprit here: https://www.githubstatus.com/incidents/tf9v5jjmq2lg