Updated Vault 1.9 documentation (#13194)

* post 1-9 doc changes

* fixed endpoint sample

* Update website/content/docs/release-notes/1.9.0.mdx

Co-authored-by: Yoko Hyakuna <yoko@hashicorp.com>

Co-authored-by: Yoko Hyakuna <yoko@hashicorp.com>

website/content/docs/concepts/client-count/faq.mdx

@@ -30,7 +30,6 @@ This FAQ section contains frequently asked questions about the client count feat
 - [Q: How can I disable the counting of client activity?](http://localhost:3000/docs/concepts/client-count/faq#q-how-can-i-disable-the-counting-of-client-activity)
 - [Q: If I request data for January 2021 - December 2021, but April’s data does not exist, what will be included in the total client count result?](#q-if-i-request-data-for-january-2021-december-2021-but-april-s-data-does-not-exist-what-will-be-included-in-the-total-client-count-result)
 - [Q: How can I configure the activity for log retention?](#q-how-can-i-configure-the-activity-for-log-retention)
-- [Q: What do we recommend in situations where high cardinality aliases occur?](#q-what-do-we-recommend-in-situations-where-high-cardinality-aliases-occur)
 - [Q: Do child namespaces create duplicate tokens?](#q-do-child-namespaces-create-duplicate-tokens)
 
 
@@ -201,7 +200,7 @@ You can disable the count of client activity by using the enabled parameter in t
 
 ### Q: If I request data for January 2021 - December 2021, but April’s data does not exist, what will be included in the total client count result?
 
-In this scenario where you requested data for January 2021 through December 2021, and April's data does not exist because tracking was disabled for that particular month while other months have data, Vault will only return the largest contiguous set of data, so in this case, data will only be returned for May 2021 through December 2021.
+In this scenario where you requested data for January 2021 through December 2021, and April's data does not exist because tracking was disabled for that particular month while other months have data, Vault will only return the most recent contiguous set of data, so in this case, data will only be returned for May 2021 through December 2021.
 
 ### Q: How can I configure the activity for log retention?
 

website/content/docs/release-notes/1.9.0.mdx

@@ -47,19 +47,19 @@ The [KMS Engine for GCP](https://www.vaultproject.io/docs/secrets/gcpkms) provid
 
 ## Other Features and Enhancements
 
-This section describes other features and enhancments introduced as part of the Vault 1.9 release.
+This section describes other features and enhancements introduced as part of the Vault 1.9 release.
 
 ### Vaut Agent improvements
 
-Improvements were made to the Vault Agent Cache to ensure that [consul-template is always routed through the Vault Agent cache](https://github.com/hashicorp/vault/pull/12762), therefore, eliminating the need for listeners to be defined in the Vault Agent for just templating.
+Improvements were made to the Vault Agent Cache to ensure that [consul-template is always routed through the Vault Agent cache](/docs/agent/template), therefore, eliminating the need for listeners to be defined in the Vault Agent for just templating.
 
 ### Customized username generation for database dynamic credentials
 
 This feature enables customization of username for database dynamic credentials. This feature helps customers better manage and correlate usernames for various actions such as troubleshooting, etc. Vault 1.9 supports Postgres, MSSQL, MySQL, Oracle, MongoDB.
 
 ### Customizable HTTP headers for Vault
 
-This [features](https://github.com/hashicorp/vault/pull/12485) allows security operators to configure [custom response headers](/docs/configuration/listener/tcp) to HTTP root path (/) and API endpoints (/v1/*), in addition to the previously supported UI paths through the server HCL configuration file.
+This feature allows security operators to configure [custom response headers](/docs/configuration/listener/tcp) to HTTP root path (`/`) and API endpoints (`/v1/*`), in addition to the previously supported UI paths through the server HCL configuration file.
 
 ### Support for IBM s390X CPU architecture
 
@@ -82,12 +82,12 @@ The following enhancement are included:
 
 ### Customized metadata for KV
 
-This [enhancement](https://github.com/hashicorp/vault/pull/12907) provides the ability to set version-agnostic custom key metadata for Vault KVv2 secrets via a metadata endpoint. This custom metadata is also visible in the UI.
+This [enhancement](https://www.vaultproject.io/api-docs/secret/kv/kv-v2) provides the ability to set version-agnostic custom key metadata for Vault KVv2 secrets via a metadata endpoint. This custom metadata is also visible in the UI.
 
 ## UI Enhancements
 ### Expanding the UI for more DB secrets engines
 
-We have been adding support for DB secrets engines in the UI over the past few releases. In the Vault 1.9 release, we have added support for [Oracle](https://github.com/hashicorp/vault/pull/12752) and [ElasticSearch](https://github.com/hashicorp/vault/pull/12672) and [PostgresSQL](https://github.com/hashicorp/vault/pull/12945) database secrets engines in the UI.
+We have been adding support for DB secrets engines in the UI over the past few releases. In the Vault 1.9 release, we have added support for [Oracle](/docs/secrets/databases/oracle) and [ElasticSearch](/docs/secrets/databases/elasticdb) and [PostgresSQL](/docs/secrets/databases/postgresql) database secrets engines in the UI.
 
 ### PKI certificate metadata
 
@@ -101,7 +101,7 @@ This feature provides a more streamlined method for managing [KV v2 secrets](htt
 
 ### Vault as an OIDC Provider
 
-Vault can now act as an OIDC Provider so applications can leverage the pre-existing [Vault identities](https://www.vaultproject.io/api-docs/secret/identity) to authenticate and authorize into applications.
+Vault can now act as an OIDC Provider so applications can leverage the pre-existing [Vault identities](/api-docs/secret/identity) to authenticate into applications.
 
 ## Breaking Changes