feat: refactor redis-ha NetworkPolicy to include egress rules (#9968)

[34fathombelow]

Fixes #9968

This policy change includes egress rules to only allow DNS traffic outbound and maintain inter-Redis and Sentinel connectivity. argocd-redis-ha-server & argocd-redis-ha-proxy should not be allowed to communicate with other pods in the cluster to prevent lateral movement in the event a redis pod is breached.

kubectl describe networkpolicies.networking.k8s.io argocd-redis-ha-server-network-policy 

Name:         argocd-redis-ha-server-network-policy
Namespace:    argocd
Created on:   2022-08-05 17:36:44 -0700 PDT
Labels:       <none>
Annotations:  <none>
Spec:
  PodSelector:     app.kubernetes.io/name=argocd-redis-ha
  Allowing ingress traffic:
    To Port: 6379/TCP
    To Port: 26379/TCP
    From:
      PodSelector: app.kubernetes.io/name=argocd-redis-ha-haproxy
    From:
      PodSelector: app.kubernetes.io/name=argocd-redis-ha
  Allowing egress traffic:
    To Port: 6379/TCP
    To Port: 26379/TCP
    To:
      PodSelector: app.kubernetes.io/name=argocd-redis-ha
    ----------
    To Port: 53/UDP
    To Port: 53/TCP
    To:
      NamespaceSelector: <none>
  Policy Types: Ingress, Egress

kubectl describe networkpolicies.networking.k8s.io argocd-redis-ha-proxy-network-policy

Name:         argocd-redis-ha-proxy-network-policy
Namespace:    argocd
Created on:   2022-08-05 17:36:44 -0700 PDT
Labels:       <none>
Annotations:  <none>
Spec:
  PodSelector:     app.kubernetes.io/name=argocd-redis-ha-haproxy
  Allowing ingress traffic:
    To Port: 6379/TCP
    To Port: 26379/TCP
    From:
      PodSelector: app.kubernetes.io/name=argocd-server
    From:
      PodSelector: app.kubernetes.io/name=argocd-repo-server
    From:
      PodSelector: app.kubernetes.io/name=argocd-application-controller
  Allowing egress traffic:
    To Port: 6379/TCP
    To Port: 26379/TCP
    To:
      PodSelector: app.kubernetes.io/name=argocd-redis-ha
    ----------
    To Port: 53/UDP
    To Port: 53/TCP
    To:
      NamespaceSelector: <none>
  Policy Types: Ingress, Egress

Signed-off-by: Justin Marquis 34fathombelow@protonmail.com

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[codecov]

Codecov Report

Merging #10226 (b8cd5e3) into master (3520dfc) will increase coverage by 0.05%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #10226      +/-   ##
==========================================
+ Coverage   45.93%   45.98%   +0.05%     
==========================================
  Files         227      226       -1     
  Lines       27419    27413       -6     
==========================================
+ Hits        12594    12605      +11     
+ Misses      13114    13094      -20     
- Partials     1711     1714       +3     

Impacted Files	Coverage Δ
controller/state.go	73.89% <0.00%> (-0.33%)	⬇️
controller/sync.go	56.09% <0.00%> (ø)
cmd/util/cluster.go	41.17% <0.00%> (ø)
pkg/apiclient/apiclient.go	0.96% <0.00%> (ø)
reposerver/repository/repository.go	64.30% <0.00%> (ø)
cmd/argocd/commands/admin/settings_rbac.go	23.80% <0.00%> (ø)
util/argo/managedfields/parser.go
cmd/argocd/commands/app.go	20.44% <0.00%> (+0.06%)	⬆️
util/argo/diff/diff.go	52.41% <0.00%> (+0.20%)	⬆️
util/settings/settings.go	51.42% <0.00%> (+0.51%)	⬆️
... and 1 more

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