Simplify the KubernetesClient spec

Only verify the arguments we actually care about.

spec/lib/quality/kubernetes_client_spec.rb

@@ -3,29 +3,23 @@
 require 'spec_helper'
 
 RSpec.describe Quality::KubernetesClient do
-  let(:namespace) { 'review-apps-ee' }
-  let(:release_name) { 'my-release' }
-
-  subject { described_class.new(namespace: namespace) }
+  subject { described_class.new(namespace: 'review-apps-ee') }
 
   describe '#cleanup' do
-    it 'calls helm list with default arguments' do
-      expect(Gitlab::Popen).to receive(:popen_with_detail)
-        .with([
-          %(kubectl),
-          %(-n "#{namespace}" get ingress,svc,pdb,hpa,deploy,statefulset,job,pod,secret,configmap,pvc,secret,clusterrole,clusterrolebinding,role,rolebinding,sa 2>&1),
-          '|',
-          %(grep "#{release_name}"),
-          '|',
-          "awk '{print $1}'",
-          '|',
-          %(xargs kubectl -n "#{namespace}" delete),
-          '||',
-          'true'
-        ])
-        .and_return(Gitlab::Popen::Result.new([], ''))
+    it 'calls kubectl with the correct arguments' do
+      # popen_with_detail will receive an array with a bunch of arguments; we're
+      # only concerned with it having the correct namespace and release name
+      expect(Gitlab::Popen).to receive(:popen_with_detail) do |args|
+        expect(args)
+          .to satisfy_one { |arg| arg.start_with?('-n "review-apps-ee" get') }
+        expect(args)
+          .to satisfy_one { |arg| arg == 'grep "my-release"' }
+        expect(args)
+          .to satisfy_one { |arg| arg.end_with?('-n "review-apps-ee" delete') }
+      end
 
-      subject.cleanup(release_name: release_name)
+      # We're not verifying the output here, just silencing it
+      expect { subject.cleanup(release_name: 'my-release') }.to output.to_stdout
     end
   end
 end