flake: coderd: TestWorkspaceWatcher

Seen here: https://github.com/coder/coder/actions/runs/14194339815/job/39765912427

```
=== FAIL: coderd  (0.00s)
panic: test timed out after 10m0s
	running tests:
		TestWorkspaceWatcher (9m54s)
[...]
```

Logs: https://gist.githubusercontent.com/johnstcn/7cd8e954ca51bb8d84612b3825f1c31c/raw/e803449f445546d60d7de6e2709fe307ea0d33f8/gistfile1.txt

