Fix issue with fetching the namespace key

[rak-phillip]

Summary

This ensure that the v ref is properly accessed using v.value when attempting to get the namespace via key.

Fixes #16342

Occurred changes and/or fixed issues

• Access the v ref using v.value when fetching the namespace key
• Unit test the change

Technical notes summary

A ref was originally being passed to the get() method, the value was unable to be read and this returned undefined. The namespace will be set to "Default" when the get() method returns undefined.

Areas or cases that should be tested

See issue and kubewarden: rancher/kubewarden-ui#1387 (comment)

Areas which could experience regressions

This should be resolving a previous regression.

Screenshot/Video

Checklist

• The PR is linked to an issue and the linked issue has a Milestone, or no issue is needed
• The PR has a Milestone
• The PR template has been filled out
• The PR has been self reviewed
• The PR has a reviewer assigned
• The PR has automated tests or clear instructions for manual tests and the linked issue has appropriate QA labels, or tests are not needed
• The PR has reviewed with UX and tested in light and dark mode, or there are no UX changes
• The PR has been reviewed in terms of Accessibility
• The PR has considered, and if applicable tested with, the three Global Roles Admin, Standard User and User Base

[cnotv]

I do not grasp entirely the logic, but the change seems quite obviously better to me, plus it has a test.

Thanks for the help!

LGTM