`NO_NAVSTART` in api tests and smoke tests

Retries added to unblock CI: https://github.com/GoogleChrome/lighthouse/pull/15378

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Example failure: https://github.com/GoogleChrome/lighthouse/actions/runs/5871078774/job/15919549134?pr=15378

Example failure trace: https://trace.cafe/t/K4uwDnVkKA

- Entire main thread track is missing for some reason.
- Navigation tests fail with `NO_NAVSTART` on a bunch of audits
- Timespan tests fail because the INP event is missing, making the INP audits N/A

`NO_NAVSTART` also appears on smoke tests: https://github.com/GoogleChrome/lighthouse/actions/runs/5894225760/job/15987413301?pr=15353

Start with the linked CI runs and trace, then reproduce the navigation, timespan, and smoke-test failures. Investigate why the main-thread track and navigation start are missing, and verify that the affected audits receive the expected navigation and INP data without retries.

Written by the indexing model from the issue text.