Reduce text duplication in documentation

based on review.

Thanks to @manics

Author: rgaiacs

docs/source/zero-to-binderhub/setup-binderhub.rst

@@ -112,34 +112,11 @@ Create ``config.yaml``
 
 Create a file called ``config.yaml``.
 
-Exposing JupyterHub
-~~~~~~~~~~~~~~~~~~~
+Exposing JupyterHub and BinderHub
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-By default, JupyterHub is exposed as a ``LoadBalancer``.
-If you want to expose JupyterHub using an ingress controller,
-you need to add::
-
-    jupyterhub:
-      proxy:
-        service:
-        type: ClusterIP
-      ingress:
-        enabled: true
-        annotations:
-          # replace with your ingress class
-          kubernetes.io/ingress.class: "nginx"
-        hosts:
-          - jupyterhub.XXX.XXX.XXX.XXX.nip.io
-
-The above snippet assumes that you are using `Ingress NGINX Controller <https://kubernetes.github.io/ingress-nginx/>`_
-and uses `nip.io <https://nip.io/>`_ to provide you with a temporary domain
-to the IP ``XXX.XXX.XXX.XXX``.
-
-Exposing BinderHub
-~~~~~~~~~~~~~~~~~~
-
-By default, BinderHub is exposed as ``LoadBalancer``.
-If you want to expose BinderHub using a ingress controller,
+By default, JupyterHub and BinderHub is exposed as a ``LoadBalancer``.
+If you want to expose JupyterHub and BinderHub using an ingress controller,
 you need to add::
 
     service:
@@ -148,17 +125,31 @@ you need to add::
     ingress:
       enabled: true
       annotations:
-        # use the shared ingress-nginx
+        # replace with your ingress class
         kubernetes.io/ingress.class: "nginx"
       https:
           # This is unsafe! Only se for local development
           enabled: false
       hosts:
+        # replace with your domain for BinderHub
         - binderhub.XXX.XXX.XXX.XXX.nip.io
 
+    jupyterhub:
+      proxy:
+        service:
+        type: ClusterIP
+      ingress:
+        enabled: true
+        annotations:
+          # replace with your ingress class
+          kubernetes.io/ingress.class: "nginx"
+        hosts:
+          # replace with your domain for JupyterHub
+          - jupyterhub.XXX.XXX.XXX.XXX.nip.io
+
 The above snippet assumes that you are using `Ingress NGINX Controller <https://kubernetes.github.io/ingress-nginx/>`_
 and uses `nip.io <https://nip.io/>`_ to provide you with a temporary domain
-to the IPv6 ``XXX.XXX.XXX.XXX``.
+to the IP ``XXX.XXX.XXX.XXX``.
 
 Expand ``config.yaml``
 ----------------------