Fix TestSchedulerWait with a flaky behaviour

[boulder225]

🎯 Problem to be solved

The test TestSchedulerWait has a flaky behaviour. It fails intermittently when run with the -race and -count flags locally.

🛠️ Proposed solution

• [ ] Investigate the test's implementation to identify any race conditions or timing dependencies.
• [ ] Run the test with increased verbosity to gather detailed logs during failure instances.
• [ ] Implement fixes to address identified race conditions or timing issues.