Add coverage for `remote_interaction_helper` (#28002)

spec/requests/remote_interaction_helper_spec.rb

@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe 'Remote Interaction Helper' do
+  describe 'GET /remote_interaction_helper' do
+    it 'returns http success' do
+      get remote_interaction_helper_path
+
+      expect(response)
+        .to have_http_status(200)
+        .and render_template(:index, layout: 'helper_frame')
+        .and have_attributes(
+          headers: include(
+            'X-Frame-Options' => 'SAMEORIGIN',
+            'Referrer-Policy' => 'no-referrer',
+            'Content-Security-Policy' => expected_csp_headers
+          )
+        )
+    end
+  end
+
+  private
+
+  def expected_csp_headers
+    <<~CSP.squish
+      default-src 'none'; frame-ancestors 'self'; form-action 'none'; script-src 'self' https://cb6e6126.ngrok.io 'wasm-unsafe-eval'; connect-src https:
+    CSP
+  end
+end