Adding AD lifetime period of an old password note to Vault LDAP secrets Engine API Documentation

[gerardma77]

Description

This PR adds an AD lifetime period of an old password note to Vault LDAP secrets Engine API Documentation.

TODO only if you're a HashiCorp employee

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  • If this fixes a critical security vulnerability or severity 1 bug, it will also need to be backported to the current LTS versions of Vault. To ensure this, use all available enterprise labels.
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  break any tests. Sometimes ENT only tests rely on public functions in CE
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CI Results:
All Go tests succeeded! ✅

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[kwagga]

LGTM - Change the wording slightly.