Issue title: Test Flake: Unit test cmd/entrypoint TestRealRunnerTimeout
 Issue body: Sadly not much info present in log file:
```
=== RUN   TestRealRunnerTimeout
    runner_test.go:37: step didn't timeout
--- FAIL: TestRealRunnerTimeout (0.03s)
```

/kind flake
/priority important-soon
 Comments: 
 Comment 0: Issues go stale after 90d of inactivity.
Mark the issue as fresh with `/remove-lifecycle stale` with a justification.
Stale issues rot after an additional 30d of inactivity and eventually close.
If this issue is safe to close now please do so with `/close` with a justification.
If this issue should be exempted, mark the issue as frozen with `/lifecycle frozen` with a justification.

/lifecycle stale

Send feedback to [tektoncd/plumbing](https://github.com/tektoncd/plumbing).
 Comment 1: /lifecycle frozen

I hit this one while trying to reproduce the various events-related flakes, so it's still a thing. I thought that maybe increasing the timeout in the test would help, but I seem to still be hitting it...
 Comment 2: Yeah, it failing or not depended on what I had for `-count` and the overall load on my system, not on anything flaky. Sigh. Well, it's still a flake, just one I can't come up with a fix for...
{'source': 'GithubIssues', 'repo_name_with_owner': 'tektoncd/pipeline', 'issue_id': 1158576052, 'repo_stars': 7290.0}