chore: update config of installation by Kustomize (#557)

Update default values in config file to make the installation of apisix-ingress-controller by Kustomize ready to use.

* update the default version of apisix-ingress-controller container image to keep it up-to-date
* update apisix.base_url to send requests to the correct APISIX address
* add apisix.admin_key to configure APISIX Admin API access token. This avoids 401 Authenticaion Required error when invoking APISIX Admin API
diff --git a/samples/deploy/configmap/apisix-ingress-cm.yaml b/samples/deploy/configmap/apisix-ingress-cm.yaml
index f9f04ba..5c98ff8 100644
--- a/samples/deploy/configmap/apisix-ingress-cm.yaml
+++ b/samples/deploy/configmap/apisix-ingress-cm.yaml
@@ -46,8 +46,9 @@
 
    # APISIX related configurations.
    apisix:
-     base_url: "http://127.0.0.1:9080/apisix/admin" # the APISIX admin api / manager api
+     base_url: "http://apisix-admin:9180/apisix/admin" # the APISIX admin api / manager api
                                               # base url, it's required.
+     admin_key: "edd1c9f034335f136f87ad84b625c8f1"
 kind: ConfigMap
 metadata:
   name: apisix-ingress-cm
diff --git a/samples/deploy/deployment/ingress-controller.yaml b/samples/deploy/deployment/ingress-controller.yaml
index eaca8dd..f6ab334 100644
--- a/samples/deploy/deployment/ingress-controller.yaml
+++ b/samples/deploy/deployment/ingress-controller.yaml
@@ -41,7 +41,7 @@
       hostNetwork: true
       dnsPolicy: ClusterFirstWithHostNet
       containers:
-      - image: apache/apisix-ingress-controller:0.1.0
+      - image: apache/apisix-ingress-controller:1.0.0
         imagePullPolicy: IfNotPresent
         name: ingress-controller
         ports: