Merge Openbao and Hashicorp Vault playbooks (#1740)

* Add variable to choose CA secret store

* Add set of merged playbooks for OpenBao and Vault

* Remove vault and openbao specific playbooks

* Merge openbao and vault doc

* Add reno

* Fix wording in reno and docs

Co-authored-by: Alex-Welsh <112560678+Alex-Welsh@users.noreply.github.com>

---------

Co-authored-by: Alex-Welsh <112560678+Alex-Welsh@users.noreply.github.com>

Author: seunghun1ee

doc/source/configuration/index.rst

@@ -14,7 +14,6 @@ the various features provided.
    cephadm
    monitoring
    openbao
-   vault
    wazuh
    walled-garden
    security-hardening