[Prod] Fixes from accessibility review

[thewatermethod]

Description of change

Fix issues found during accessibility review:

• Resource repeater should use dynamic error text insertion instead of conditionally displaying the error message, since browsers only read off updates to elements with role alert and not creation
• Fixes a bug with disappearing root causes on FEI goals created on AR
• Fixes a bug with an input not properly associated with a label

How to test

• Confirm that the resource repeater error is announced
• Confirm that creating an FEI goal on an activity report allows you to edit the root causes
• Confirm that the event creator has a label "for" matching the input id

Issue(s)

• https://jira.acf.gov/browse/TTAHUB-3415

Checklists

Every PR

• Meets issue criteria
• JIRA ticket status updated
• Code is meaningfully tested
• Meets accessibility standards (WCAG 2.1 Levels A, AA)
• API Documentation updated
• Boundary diagram updated
• Logical Data Model updated
• Architectural Decision Records written for major infrastructure decisions
• UI review complete

Before merge to main

• OHS demo complete
• Ready to create production PR

Production Deploy

• Staging smoke test completed

After merge/deploy

• Update JIRA ticket status