Fix inaccuracies in ingress dest CA cert docs

This commit fixes bug 2110059.

https://bugzilla.redhat.com/show_bug.cgi?id=2110059

* modules/nw-ingress-creating-a-route-via-an-ingress.adoc: Change "oc
`create`" to "`oc create`".
* modules/nw-ingress-reencrypt-route-custom-cert.adoc: Change "an route" to
"a route".  Replace "certificate (CA)" with "destination CA certificate".
State that the user *may* (not *must*) specify a certificate/key pair.
Change "Annotations:" to "annotations:" in the example yaml.

Author: Miciah

modules/nw-ingress-creating-a-route-via-an-ingress.adoc

@@ -10,7 +10,7 @@ Some ecosystem components have an integration with Ingress resources but not wit
 
 .Procedure
 
-. Define an Ingress object in the {product-title} console or by entering the oc `create` command:
+. Define an Ingress object in the {product-title} console or by entering the `oc create` command:
 +
 .YAML Definition of an Ingress
 [source,yaml]

modules/nw-ingress-reencrypt-route-custom-cert.adoc

@@ -6,10 +6,10 @@
 [id="creating-re-encrypt-route-with-custom-certificate_{context}"]
 = Creating a route using the destination CA certificate in the Ingress annotation
 
-The `route.openshift.io/destination-ca-certificate-secret` annotation can be used on an Ingress object to define an route with a custom certificate (CA).
+The `route.openshift.io/destination-ca-certificate-secret` annotation can be used on an Ingress object to define a route with a custom destination CA certificate.
 
 .Prerequisites
-* You must have a certificate/key pair in PEM-encoded files, where the certificate is valid for the route host.
+* You may have a certificate/key pair in PEM-encoded files, where the certificate is valid for the route host.
 * You may have a separate CA certificate in a PEM-encoded file that completes the certificate chain.
 * You must have a separate destination CA certificate in a PEM-encoded file.
 * You must have a service that you want to expose.
@@ -42,7 +42,7 @@ apiVersion: route.openshift.io/v1
 kind: Route
 metadata:
   name: frontend
-  Annotations:
+  annotations:
     route.openshift.io/termination: reencrypt
     route.openshift.io/destination-ca-certificate-secret: secret-ca-cert
 spec: