[website] implement postgres/secrets redirect (#8208)

* add secrets/postgresql redirect

* change name of old path

* ensure deprecated pages are not indexed by search engines

* remove deprecated page from navigation

website/_redirects

@@ -184,3 +184,6 @@
 /intro/getting-started/deploy.html https://learn.hashicorp.com/vault/getting-started/deploy
 /intro/getting-started/apis.html https://learn.hashicorp.com/vault/getting-started/apis
 /intro/getting-started/next-steps.html https://learn.hashicorp.com/vault/getting-started/next-steps
+
+/docs/secrets/postgresql/index.html     /docs/secrets/databases/postgresql
+/docs/secrets/postgresql                /docs/secrets/databases/postgresql

website/components/docs-page/index.jsx

@@ -25,6 +25,7 @@ export default function DocsPage({
             key="description"
           />
         )}
+        {pageMeta.deprecated && <meta name="robots" content="noindex" />}
       </Head>
       <div className="content-wrap g-container">
         <div id="sidebar" role="complementary">

website/data/docs-navigation.js

@@ -248,8 +248,7 @@ export default [
       { category: 'cassandra' },
       { category: 'mongodb' },
       { category: 'mssql' },
-      { category: 'mysql' },
-      { category: 'postgresql' }
+      { category: 'mysql' }
     ]
   },
   {

website/pages/docs/secrets/postgresql/postgres-deprecated.mdx

@@ -2,6 +2,7 @@
 layout: docs
 page_title: PostgreSQL - Secrets Engines
 sidebar_title: PostgreSQL <sup>DEPRECATED</sup>
+deprecated: true
 description: >-
   The PostgreSQL secrets engine for Vault generates database credentials to
   access PostgreSQL.