`MutableSuiteTest` is flaky

The MutableSuiteTest for sleeping is flaky:

  test("sleeping") {
    for {
      before <- CatsUnsafeRun.realTimeMillis
      _      <- CatsUnsafeRun.sleep(1.seconds)
      after  <- CatsUnsafeRun.realTimeMillis
    } yield expect(after - before >= 1000)
  }

The test suite is run by DogFoodTests. This failed in Github Actions:
https://github.com/typelevel/weaver-test/actions/runs/17489340107/job/49675350638#step:10:135

 [info] *************FAILURES**************
[info] weaver.framework.test.DogFoodTests
[info] - test suite reports successes events 3s
[info]   weaver.framework.test.Meta$MutableSuiteTest:TestSelector(sleeping) failed with Failure (modules/framework-cats/shared/src/test/scala/DogFoodTests.scala:22)
[info] 
[info]   modules/framework-cats/shared/src/test/scala/DogFoodTests.scala:22
[info]         case (_, events) => forEach(events)(isSuccess)
[info]                                                     ^

Start with the sleeping test in modules/framework-cats/shared/src/test/scala/MutableSuiteTest.scala and inspect how it is exercised by modules/framework-cats/shared/src/test/scala/DogFoodTests.scala. Reproduce the GitHub Actions failure if possible and verify that the sleeping test and DogFoodTests remain reliable across repeated runs.