Create egressgateway usage not update

[lou-lan]

Create egressgateway, the egressgateway node selector not match any node, the egressgateway CR not update IPPool usage.

apiVersion: egressgateway.spidernet.io/v1beta1
kind: EgressGateway
metadata:
  annotations:
    description: ""
  name: egw2
spec:
  ippools:
    ipv4:
    - 10.6.92.5/24
  nodeSelector:
    selector:
      matchLabels:
        egress: "true"

NAME            IPV4DEFAULTEIP   IPV6DEFAULTEIP   CLUSTERDEFAULT   IPV4TOTAL   IPV4FREE   IPV6TOTAL   IPV6FREE
egw2             10.6.92.188                                        

[lou-lan]

Add a e2e test for this case.

[weizhoublue]

add a test case for the fix

[lou-lan]

Updated https://github.com/spidernet-io/egressgateway/pull/1325/files#diff-97739a2284b749ae60d8b9ae757736908ae6b328c2500cfff8283c58799a0446