Backport of Update vault-plugin-auth-jwt to v0.20.3 into release/1.14.x

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

Backport

This PR is auto-generated from #26890 to be assessed for backporting due to the inclusion of the label backport/1.14.x.

🚨

Warning automatic cherry-pick of commits failed. If the first commit failed,
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The person who merged in the original PR is:
@thyton
This person should manually cherry-pick the original PR into a new backport PR,
and close this one when the manual backport PR is merged in.

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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This PR was generated by a GitHub Action. Full log: https://github.com/hashicorp/vault/actions/runs/9009980689

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Overview of commits

• 51c851b

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[github-actions]

CI Results:
All Go tests succeeded! ✅

[fairclothjm]

@thyton I don't think we can backport v0.20.3 of the auth jwt plugin into Vault v1.14.x. If this fix must go into 1.14, we will need to backport the fix to the plugin's v0.18.x. I have not verified the exact versions though so please double check that. Let me know if you need help!

[thyton]

@fairclothjm Thank you for pointing this out. I think the version we need v0.16.1 of the auth jwt plugin based on https://github.com/hashicorp/vault/blob/release/1.14.x/go.mod#L131

I'm closing this automated backport PR.