fix service and deployment

Author: EmilyM1

guestbook/all-in-one/redis-slave.yaml renamed to guestbook/all-in-one/redis-replica.yaml

@@ -1,39 +1,39 @@
 apiVersion: v1
 kind: Service
 metadata:
-  name: redis-slave
+  name: redis-replica
   labels:
     app: redis
-    role: slave
+    role: replica
     tier: backend
 spec:
   ports:
   - port: 6379
   selector:
     app: redis
-    role: slave
+    role: replica
     tier: backend
 ---
 apiVersion: apps/v1 #  for k8s versions before 1.9.0 use apps/v1beta2  and before 1.8.0 use extensions/v1beta1
 kind: Deployment
 metadata:
-  name: redis-slave
+  name: redis-replica
 spec:
   selector:
     matchLabels:
       app: redis
-      role: slave
+      role: replica
       tier: backend
   replicas: 2
   template:
     metadata:
       labels:
         app: redis
-        role: slave
+        role: replica
         tier: backend
     spec:
       containers:
-      - name: slave
+      - name: replica
         image: gcr.io/google_samples/gb-redisslave:v1
         resources:
           requests: