[backport v2.10.1] AKS region changes in Edit Mode

[github-actions]

This is a backport issue for #11841, automatically created via GitHub Actions workflow initiated by @gaktive

Original issue body:

Setup

• Rancher version: v2.9-0f2bd9c3cde85aa2b5270946d0cecd5c95b86fd2-head

Describe the bug

When creating an AKS cluster in a region different from the default displayed in the UI (East US) with the wrong configuration, once the user edits the cluster config, the Azure Region is set back to the default, undoing the region that the user previously selected

To Reproduce
1- Via UI, create an Azure cluster under a region other than East US with incomplete or wrong config
2- After the cluster is created, try to edit the cluster config via UI
3 - Observe that the region switches to the East US

Result
the Azure Region is set back to the default, undoing the region that the user previously selected

Expected Result
The region previously selected by the user must be preserved in the Edit form

Screenshots

Screen.Recording.2024-09-05.at.17.24.41.mov

[izaac]

Unit test coverate looks good to me, moving yo QA Working

[izaac]

Rancher version: v2.10.2-alpha1
UI Version: v2.10.2-alpha3

This is no longer reproducible with the latest alpha of the 2.10 UI. Pass ✅