Use anonymous class in base_command_spec

spec/lib/gitlab/kubernetes/helm/base_command_spec.rb

 require 'spec_helper'
 
-class TestClass
+describe Gitlab::Kubernetes::Helm::BaseCommand do
+  let(:application) { create(:clusters_applications_helm) }
+  let(:test_class) do
+    Class.new do
       include Gitlab::Kubernetes::Helm::BaseCommand
+
       def name
         "test-class-name"
       end
@@ -11,11 +15,13 @@ class TestClass
           some: 'value'
         }
       end
-end
+    end
+  end
+
+  let(:base_command) do
+    test_class.new
+  end
 
-describe Gitlab::Kubernetes::Helm::BaseCommand do
-  let(:application) { create(:clusters_applications_helm) }
-  let(:base_command) { TestClass.new }
   subject { base_command }
 
   it_behaves_like 'helm commands' do