e2e: TestExamples is flaky

[vdemeester]

Some e2e examples test are flaky.

2025-10-07T20:38:25.3636724Z     --- FAIL: TestExamples/v1/pipelineruns/pipelinerun-with-task-timeout-override (20.92s)
...
2025-10-07T20:38:25.3692307Z     --- FAIL: TestExamples/v1/pipelineruns/beta/pipelinerun-with-matrix (605.80s)
...
2025-10-08T09:40:48.9826519Z     --- FAIL: TestExamples/v1/pipelineruns/using-retries-and-retry-count-variables (600.39s)

See

• https://github.com/tektoncd/pipeline/actions/runs/18324465586/job/52185466094?pr=9047
• https://github.com/tektoncd/pipeline/actions/runs/18324465586/job/52185466098?pr=9047
• https://github.com/tektoncd/pipeline/actions/runs/18339183125/job/52230530489?pr=9067