ci: Upgrade AWS credentials action

[jygong-amazon]

ℹ️ Description

Upgrade aws-actions/configure-aws-credentials from v2 to v6.3.0 in the daily workflow. Version 2 runs under GitHub's forced Node 24 compatibility mode and masks some OIDC failures with Cannot read properties of undefined (reading 'message'). Version 6.3.0 declares Node 24 and preserves the existing role-to-assume and aws-region inputs.

Issue #, if available

Related: scheduled run 35337891143 and ORR action item

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update
  • README update
  • CHANGELOG update
  • guides update
• This change requires a dependency update
  • Amazon Chime SDK Media
  • Other (GitHub Actions credential dependency; no product legal-document impact)

🧪 How Has This Been Tested?

• Workflow YAML parses successfully.
• Verified v6.3.0 declares the Node 24 runtime.
• Verified v6.3.0 retains role-to-assume and aws-region inputs.
• Verified permissions: id-token: write and the existing role/region values are unchanged.
• Live OIDC validation is pending on master; the role trust policy does not authorize feature-branch subjects.

Unit test coverage

Not applicable to a one-line workflow dependency update.

Additional Manual Test

• Pause and resume remote video — not applicable to workflow-only change
• Switch local camera — not applicable to workflow-only change
• Rotate screen back and forth — not applicable to workflow-only change

📱 Screenshots, if available

Not applicable.

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.