[JENKINS-38673] update tests to run more stable

[scherler]

Description

See JENKINS-38673.

Submitter checklist

• Link to JIRA ticket in description, if appropriate.
• Change is code complete and matches issue description
• Reviewer's manual test instructions provided in PR description. See Reviewer's first task below.
• Ran Acceptance Test Harness against PR changes.

Reviewer checklist

• Run the changes and verified the change matches the issue description
• Reviewed the code
• Verified that the appropriate tests have been written or valid explanation given

@jenkinsci/code-reviewers @reviewbybees

[ghost]

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