[Security Solution][Detections] Fix test failure due to race condition

[rylnd]

Summary

This fixes an intermittent test failure caused by a race condition between tests and the global jsdom object.

These tests are already skipped on 7.9, so no need to backport there.

Checklist

for features that require explanation or tutorials

• Unit or functional tests were updated or added to match the most common scenarios

For maintainers

• This was checked for breaking API changes and was labeled appropriately

[rylnd]

Closing in favor of #73639

[kibanamachine]

💔 Build Failed

• continuous-integration/kibana-ci/pull-request
• Commit: 9e87581
• Pipeline Steps (look for red circles / failed steps)
• Interpreting CI Failures

Failed CI Steps

• Execute kibana-intake
• Report failed tests, if necessary

Build metrics

✅ unchanged

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@elasticmachine merge upstream