Fix Ingress resources in docs (#7579)

* fix Ingress resources in docs

Signed-off-by: Gerald Pape <gerald@giantswarm.io>

* move to ingressClassName

* fix more Ingress resource examples

* empty commit

Signed-off-by: Gerald Pape <gerald@giantswarm.io>

* make NOTES.txt aware of version + add notice about ingress version to examples main page

* add link to legacy documentation

Signed-off-by: Gerald Pape <gerald@giantswarm.io>

docs/user-guide/ingress-path-matching.md

@@ -22,6 +22,7 @@ metadata:
   annotations:
     nginx.ingress.kubernetes.io/use-regex: "true"
 spec:
+  ingressClassName: nginx
   rules:
   - host: test.com
     http:
@@ -59,6 +60,7 @@ kind: Ingress
 metadata:
   name: test-ingress-1
 spec:
+  ingressClassName: nginx
   rules:
   - host: test.com
     http:
@@ -87,6 +89,7 @@ metadata:
   annotations:
     nginx.ingress.kubernetes.io/rewrite-target: /$1
 spec:
+  ingressClassName: nginx
   rules:
   - host: test.com
     http:
@@ -144,6 +147,7 @@ metadata:
   annotations:
     nginx.ingress.kubernetes.io/use-regex: "true"
 spec:
+  ingressClassName: nginx
   rules:
   - host: test.com
     http: