Automation: Remove orphaned cloud creds before running test

[yonasberhe23]

Summary

Fixes #rancher/qa-tasks#2043

Problem
A e2e test (cypress/e2e/tests/pages/fleet/fleet-clusters.spec.ts) creates an AWS cloud credential during setup but doesn't clean it up, leaving orphaned credentials that can affect subsequent test runs.

Solution

• Track the cloud credential ID created during cluster setup and delete it in the after hook cleanup.
• As fallback, clean up any orphaned Amazon cloud credentials before test execution in cloud-credential.spec.ts

Screenshot/Video

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[a-arias]

Code reviewed and no errors found.