Backport of Duplicate groups creation bug into release/1.12.x

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

Backport

This PR is auto-generated from #20964 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:
@akshya96
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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https://hashicorp.atlassian.net/browse/VAULT-16649
Vault does not prevent the creation of duplicate groups when multiple "create group" requests with the same group name are sent simultaneously to different nodes. The issue arises because Vault relies on the view of MemDB from IdentityStore, which is independent for each node, to check for the presence of another group with the same name. As a result, when requests occur within a short time frame, the MemDB on each node may not have the group names.

Currently, the request is only forwarded to the active node for writing to storage based on the ID i.e, as part of UpsertGroupInTxn function, we would only forward the write to storage request using SendGroupUpdate https://github.com/hashicorp/vault-enterprise/blob/5e4c01ae563d2ad3f4138171e95cb6bdb2ee9e20/vault/identity_store_util.go#LL1826C1-L1834C4.

Approved ent PR: https://github.com/hashicorp/vault-enterprise/pull/4137

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Overview of commits

• 8931e47

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