Backport of OpenAPI: Separate ListOperation from ReadOperation into release/1.14.x

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

Backport

This PR is auto-generated from #21723 to be assessed for backporting due to the inclusion of the label backport/1.14.x.

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The person who merged in the original PR is:
@averche
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.

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

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Historically, since Vault's ReadOperation and ListOperation both map to the HTTP GET method, their representation in the generated OpenAPI has been a bit confusing.

This was partially mitigated some time ago, by making the list query parameter express whether it was required or optional - but only in a way useful to human readers - the human had to know, for example, that the schema of the response body would change depending on whether list was selected.

Now that there is an effort underway to automatically generate API clients from the OpenAPI spec, we have a need to fix this more comprehensively. Fortunately, we do have a means to do so - since Vault has opinionated treatment of trailing slashes, linked to operations being list or not, we can use an added trailing slash on the URL path to separate list operations in the OpenAPI spec.

This PR implements that, and then fixes various OpenAPI DisplayAttrs consequential to this change.

See also hashicorp/vault-client-go#174, a bug which will be fixed by this work.

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Overview of commits

• e47dd9d

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[mladlow]

@averche do you happen to know if this should be merged or closed?

[stevendpclark]

Closing as we don't maintain 1.14 anymore.