Convert api/oembed controller spec to request spec (#31605)

spec/controllers/api/oembed_controller_spec.rb

@@ -1,22 +0,0 @@
-# frozen_string_literal: true
-
-require 'rails_helper'
-
-RSpec.describe Api::OEmbedController do
-  render_views
-
-  let(:alice)  { Fabricate(:account, username: 'alice') }
-  let(:status) { Fabricate(:status, text: 'Hello world', account: alice) }
-
-  describe 'GET #show' do
-    before do
-      request.host = Rails.configuration.x.local_domain
-      get :show, params: { url: short_account_status_url(alice, status) }, format: :json
-    end
-
-    it 'returns private cache control headers', :aggregate_failures do
-      expect(response).to have_http_status(200)
-      expect(response.headers['Cache-Control']).to include('private, no-store')
-    end
-  end
-end