Add new host discovery documentation layout (#3429)

* Add new host discovery documentation layout

Co-authored-by: Dan Heath <76443935+Dan-Heath@users.noreply.github.com>

website/data/docs-nav-data.json

@@ -136,10 +136,6 @@
         "title": "Identity and access management",
         "path": "concepts/iam"
       },
-      {
-        "title": "Host discovery",
-        "path": "concepts/host-discovery"
-      },
       {
         "title": "Credential management",
         "path": "concepts/credential-management"
@@ -148,6 +144,23 @@
         "title": "Auditing",
         "path": "concepts/auditing"
       },
+      {
+        "title": "Host discovery",
+        "routes": [
+          {
+            "title": "Overview",
+            "path": "concepts/host-discovery"
+          },
+          {
+            "title": "AWS dynamic hosts",
+            "path": "concepts/host-discovery/aws"
+          },
+          {
+            "title": "Azure dynamic hosts",
+            "path": "concepts/host-discovery/azure"
+          }
+        ]
+      },
       {
         "title": "Security",
         "routes": [