docs: Remove old annotations (argoproj#12168)

* Remove old annotations

This commit removes a few annotations and updates the secret that argocd uses for tls.

1. Removes the ingress class annotation, it's been replaced by the ingressClassName argument in the spec: https://kubernetes.io/docs/concepts/services-networking/ingress/#deprecated-annotation
2. Removes an old annotation used by cert-manager: https://cert-manager.io/docs/usage/ingress/#optional-configuration
3. Updates the serverName to the new argocd-server-tls secret.

Signed-off-by: Chris Wiggins <5607419+cwiggs@users.noreply.github.com>

* Remote whitespace

Signed-off-by: Chris Wiggins <5607419+cwiggs@users.noreply.github.com>

---------

Signed-off-by: Chris Wiggins <5607419+cwiggs@users.noreply.github.com>

docs/operator-manual/ingress.md

@@ -189,7 +189,7 @@ metadata:
     nginx.ingress.kubernetes.io/force-ssl-redirect: "true"
     nginx.ingress.kubernetes.io/ssl-passthrough: "true"
 spec:
-  ingressClassName: "nginx"
+  ingressClassName: nginx
   rules:
   - host: argocd.example.com
     http:
@@ -218,14 +218,13 @@ metadata:
   namespace: argocd
   annotations:
     cert-manager.io/cluster-issuer: letsencrypt-prod
-    kubernetes.io/tls-acme: "true"
     nginx.ingress.kubernetes.io/ssl-passthrough: "true"
     # If you encounter a redirect loop or are getting a 307 response code
     # then you need to force the nginx ingress to connect to the backend using HTTPS.
     #
     nginx.ingress.kubernetes.io/backend-protocol: "HTTPS"
 spec:
-  ingressClassName: "nginx"
+  ingressClassName: nginx
   rules:
   - host: argocd.example.com
     http:
@@ -259,7 +258,7 @@ metadata:
     nginx.ingress.kubernetes.io/force-ssl-redirect: "true"
     nginx.ingress.kubernetes.io/backend-protocol: "HTTP"
 spec:
-  ingressClassName: "nginx"
+  ingressClassName: nginx
   rules:
   - http:
       paths:
@@ -274,7 +273,7 @@ spec:
   tls:
   - hosts:
     - argocd.example.com
-    secretName: argocd-secret # do not change, this is provided by Argo CD
+    secretName: argocd-server-tls # do not change, this is provided by Argo CD
 ```
 
 gRPC Ingress:
@@ -287,7 +286,7 @@ metadata:
   annotations:
     nginx.ingress.kubernetes.io/backend-protocol: "GRPC"
 spec:
-  ingressClassName: "nginx"
+  ingressClassName: nginx
   rules:
   - http:
       paths:
@@ -302,7 +301,7 @@ spec:
   tls:
   - hosts:
     - grpc.argocd.example.com
-    secretName: argocd-secret # do not change, this is provided by Argo CD
+    secretName: argocd-server-tls # do not change, this is provided by Argo CD
 ```
 
 The API server should then be run with TLS disabled. Edit the `argocd-server` deployment to add the