move a timer cancel utterance to xfail

[chrisveilleux]

Description

One of the cancel timer tests is failing inexplicably from time to time. Move it to xfail until we can figure out the issue.

Type of PR

If your PR fits more than one category, there is a high chance you should submit more than one PR. Please consider this carefully before opening the PR.

• [ ] Bugfix
• [ ] Feature implementation
• [ ] Refactor of code (without functional changes)
• [ ] Documentation improvements
• [X] Test improvements

Testing

Timer tests should pass regularly.

Documentation

N/A

[krisgesling]

Did this already get done in #106?

[chrisveilleux]

I didn't realize you had already done it. The Jira ticket was still in "To Do" status. Closing this.