Removed s390x, linux/arm platform as docker build was crashing (#8121)

Co-authored-by: Carlos Tadeu Panato Junior <ctadeu@gmail.com>

docs/examples/customization/external-auth-headers/deploy/echo-service.yaml

@@ -1,88 +0,0 @@
-apiVersion: apps/v1
-kind: Deployment
-metadata:
-  name: demo-echo-service
-  labels:
-    k8s-app: demo-echo-service
-  namespace: default
-spec:
-  replicas: 1
-  selector:
-    matchLabels:
-      k8s-app: demo-echo-service
-  template:
-    metadata:
-      labels:
-        k8s-app: demo-echo-service
-    spec:
-      terminationGracePeriodSeconds: 60
-      containers:
-      - name: echo-service
-        image: electroma/ingress-demo-echosvc-amd64:0.1
-        ports:
-        - containerPort: 8080
-        resources:
-          limits:
-            cpu: 10m
-            memory: 20Mi
-          requests:
-            cpu: 10m
-            memory: 20Mi
----
-apiVersion: v1
-kind: Service
-metadata:
-  name: demo-echo-service
-  labels:
-    k8s-app: demo-echo-service
-  namespace: default
-spec:
-  ports:
-  - port: 80
-    targetPort: 8080
-  selector:
-    k8s-app: demo-echo-service
----
-apiVersion: networking.k8s.io/v1
-kind: Ingress
-metadata:
-  name: public-demo-echo-service
-  annotations:
-    nginx.ingress.kubernetes.io/auth-url: http://demo-auth-service.default.svc.cluster.local?code=200
-    nginx.ingress.kubernetes.io/auth-response-headers: UserID, UserRole
-  namespace: default
-spec:
-  ingressClassName: nginx
-  rules:
-  - host: public-demo-echo-service.kube.local
-    http:
-      paths:
-      - path: /
-        pathType: Prefix
-        backend:
-          service:
-            name: demo-echo-service
-            port:
-              number: 80
----
-apiVersion: networking.k8s.io/v1
-kind: Ingress
-metadata:
-  name: secure-demo-echo-service
-  annotations:
-    nginx.ingress.kubernetes.io/auth-url: http://demo-auth-service.default.svc.cluster.local
-    nginx.ingress.kubernetes.io/auth-response-headers: UserID, UserRole
-  namespace: default
-spec:
-  ingressClassName: nginx
-  rules:
-  - host: secure-demo-echo-service.kube.local
-    http:
-      paths:
-      - path: /
-        pathType: Prefix
-        backend:
-          service:
-            name: demo-echo-service
-            port:
-              number: 80