Automation: fix cloud credential test

[yonasberhe23]

Summary

Fixes #rancher/qa-tasks#2043

This PR fixes failing cloud credential tests by improving the labeled input selector to handle dynamically loaded form elements:

• Updated LabeledInputPo.byLabel() to use cy.contains() instead of .find().contains() for better reliability with asynchronous content loading.

Technical notes summary

The original selector failed because .find() has no automatic retry mechanism and only searches elements already present in the DOM. When the Access Key input loaded asynchronously (after 1 second), the selector couldn't find it. The updated approach uses cy.contains(), which automatically retries for 4 seconds until the label text appears, ensuring reliable interaction with dynamically loaded form elements.

Screenshot/Video

Checklist

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[izaac]

LGTM