Backport of ui: unload auth method when navigating away from form into release/1.12.x

[hc-github-team-secure-vault-core]

Backport

This PR is auto-generated from #18651 to be assessed for backporting due to the inclusion of the label backport/1.12.x.

WARNING automatic cherry-pick of commits failed. Commits will require human attention.

merge conflict error: POST https://api.github.com/repos/hashicorp/vault/merges: 409 Merge conflict []

The below text is copied from the body of the original PR.

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before fix:

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Overview of commits

• 9752352

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