Backport of Vault 18005 plugin api lock status into release/1.12.x

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

Backport

This PR is auto-generated from #21925 to be assessed for backporting due to the inclusion of the label backport/1.12.x.

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The person who merged in the original PR is:
@ccapurso
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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The KMIP plugin starts its own listener for which requests are not routed through Vault. Requests to this listener are not subjected to API locking if the KMIP mount resides within a namespace that has been locked. This PR introduces the ability, via the ExtendedSystemView for a plugin to determine if requests to it should be blocked based on the lock status of the namespace within it resides. A separate ENT PR will be opened that adds tests as they will require namespace functionality.

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Overview of commits

• c040f90

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CI Results:
All Go tests succeeded! ✅

[ccapurso]

We are not going to backport this to 1.12.x at this time.