limiter: support leader election

[MouceL]

set replicaCount and enable-leader-election: "on" to support leader election in limiter

apiVersion: config.netease.com/v1alpha1
kind: SlimeBoot
metadata:
  name: limiter
  namespace: mesh-operator
spec:
  replicaCount: 2
  image:
    pullPolicy: Always
    repository: docker.io/slimeio/slime-limiter
    tag:  xxxxxxxxx  ##真实镜像
  module:
    - name: limiter
      kind: limiter
      enable: true
      general:
        disableGlobalRateLimit: true
        disableAdaptive: true
        disableInsertGlobalRateLimit: true
      global:
        misc:
          enable-leader-election: "on"  
        log:
          logLevel: info
        configSources:
          - address: ss://