fix(kuma-cp): handle external services with permissive mtls (backport of #7179)

[kumahq]

Automatic cherry-pick of #7179 for branch release-2.1

Generated by action

cherry-picked commit 6e228b7
⚠️ ⚠️ ⚠️ Conflicts happened when cherry-picking! ⚠️ ⚠️ ⚠️

On branch release-2.1
Your branch is up to date with 'origin/release-2.1'.

You are currently cherry-picking commit 6e228b7e5.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	new file:   test/e2e_env/kubernetes/externalservices/permissive_mtls.go

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   pkg/xds/context/mesh_context_builder.go
	both modified:   test/e2e_env/kubernetes/kubernetes_suite_test.go