bug: Should not filter GatewayClass by Namespace

[stillfox-lee]

Issue description

create GatewayClass resource like:

apiVersion: gateway.networking.k8s.io/v1alpha2
kind: GatewayClass
metadata:
  namespace: ingress-apisix-e2e-tests-default-624859000
  name: test-gateway-class
spec:
  controllerName: apisix.apache.org/gateway-controller

GatewayClass Status still be "Waiting for controller":

❯ kubectl get gatewayclass -n ingress-apisix-e2e-tests-default-624859000 -o yaml
apiVersion: v1
items:
- apiVersion: gateway.networking.k8s.io/v1alpha2
  kind: GatewayClass
  metadata:
    annotations:
      kubectl.kubernetes.io/last-applied-configuration: |
        {"apiVersion":"gateway.networking.k8s.io/v1alpha2","kind":"GatewayClass","metadata":{"annotations":{},"name":"test-gateway-class"},"spec":{"controllerName":"apisix.apache.org/gateway-controller"}}
    creationTimestamp: "2022-11-01T07:23:37Z"
    generation: 1
    name: test-gateway-class
    resourceVersion: "5288"
    uid: 4eec3b01-632b-46c3-9376-5e0864d486cd
  spec:
    controllerName: apisix.apache.org/gateway-controller
  status:
    conditions:
    - lastTransitionTime: "1970-01-01T00:00:00Z"
      message: Waiting for controller
      reason: Waiting
      status: Unknown
      type: Accepted
kind: List
metadata:
  resourceVersion: ""

As we can see, Namespace field didn't show in the Gatewayclass resource. But event handler

apisix-ingress-controller/pkg/providers/gateway/gateway_class.go

Lines 206 to 208 in 6b38e80

	if !c.controller.NamespaceProvider.IsWatchingNamespace(key) {
	return
	}

will check namespace.
May be we should just use controllerName to filter GatewayClass resource.

Environment

• your apisix-ingress-controller version (output of apisix-ingress-controller version --long): master branch
• your Kubernetes cluster version (output of kubectl version): v1.21.1
• if you run apisix-ingress-controller in Bare-metal environment, also show your OS version (uname -a): kind

Minimal test code / Steps to reproduce

like description

Actual result

no

Error log

no

Expected result

GatewayClass Status should be updated.

[tao12345666333]

Yes
GatewayClass is cluster scoped

[stillfox-lee]

This issue was discovered when I setup e2e-test for route attachment feature. Can I fix this issue with the same PR ?(route attachment)

[tao12345666333]

Sure! Please