Restructure autofill UI tests, ensure critical tests are considered release blockers

[CDRussell]

Task/Issue URL: https://app.asana.com/1/137249556945/project/488551667048375/task/1216291993298399?focus=true
Tech Design URL (if applicable): https://app.asana.com/1/137249556945/project/481882893211075/task/1216291993298403?focus=true

Description

Restructures autofill Maestro tests so that:

• the more critical of them are treated as release blockers should they fail
• the less critical ones are run as part of the non-release-blocking workflow

Steps to test this PR

• QA Optional
• Non release blocking CI job should have passed: check status
• Will confirm release blocking part passes with the overnight orchestrator run after this is merged

[CDRussell]

• Restructure autofill UI tests, ensure critical tests are considered release blockers #9117 👈 (View in Graphite)
• develop

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