fix: Fix broken vault link (#1016)

* fix: Fix broken vault link


Co-authored-by: Mike Jang <[email protected]>

Author: JTorreG

content/includes/nim/installation/optional-steps/install-configure-vault.md

@@ -11,6 +11,6 @@ NGINX Instance Manager can use [Vault](https://www.vaultproject.io/) as a datast
 
 To install and enable Vault, follow these steps:
 
-- Follow Vault's instructions to [install Vault 1.8.8 or later](https://www.vaultproject.io/docs/install) for your distribution.
+- Follow Vault's instructions to [install Vault 1.8.8 or later](https://developer.hashicorp.com/vault/install) for your operating system.
 - Ensure you're running Vault in a [production-hardened environment](https://learn.hashicorp.com/tutorials/vault/production-hardening).
 - After installing NGINX Instance Manager, follow the steps to [configure Vault for storing secrets]({{< ref "/nim/system-configuration/configure-vault.md" >}}).