Don't include EmailHelpers manually, pick with rspec

`:mailer` is needed to pick it easily, while
`type: :mailer` is needed for picking it automatically for
tests located in spec/mailers/*_spec.rb

It's a bit complicated in spec/services/notification_service_spec.rb
but we'll leave it alone for now.

spec/models/ci/pipeline_spec.rb

 require 'spec_helper'
 
-describe Ci::Pipeline do
-  include EmailHelpers
-
+describe Ci::Pipeline, :mailer do
   let(:user) { create(:user) }
   let(:project) { create(:project) }
 
@@ -1248,8 +1246,6 @@ describe Ci::Pipeline do
       pipeline.user.global_notification_setting
         .update(level: 'custom', failed_pipeline: true, success_pipeline: true)
 
-      reset_delivered_emails!
-
       perform_enqueued_jobs do
         pipeline.enqueue
         pipeline.run

spec/models/deploy_key_spec.rb

 require 'spec_helper'
 
-describe DeployKey do
-  include EmailHelpers
-
+describe DeployKey, :mailer do
   describe "Associations" do
     it { is_expected.to have_many(:deploy_keys_projects) }
     it { is_expected.to have_many(:projects) }

spec/models/gpg_key_spec.rb

@@ -114,9 +114,7 @@ describe GpgKey do
     end
   end
 
-  describe 'notification' do
-    include EmailHelpers
-
+  describe 'notification', :mailer do
     let(:user) { create(:user) }
 
     it 'sends a notification' do

spec/models/key_spec.rb

 require 'spec_helper'
 
-describe Key do
-  include EmailHelpers
-
+describe Key, :mailer do
   describe "Associations" do
     it { is_expected.to belong_to(:user) }
   end

spec/models/project_services/pipelines_email_service_spec.rb

 require 'spec_helper'
 
-describe PipelinesEmailService do
-  include EmailHelpers
-
+describe PipelinesEmailService, :mailer do
   let(:pipeline) do
     create(:ci_pipeline, project: project, sha: project.commit('master').sha)
   end
@@ -14,10 +12,6 @@ describe PipelinesEmailService do
     Gitlab::DataBuilder::Pipeline.build(pipeline)
   end
 
-  before do
-    reset_delivered_emails!
-  end
-
   describe 'Validations' do
     context 'when service is active' do
       before do

spec/requests/api/issues_spec.rb

 require 'spec_helper'
 
-describe API::Issues do
-  include EmailHelpers
-
+describe API::Issues, :mailer do
   set(:user) { create(:user) }
   set(:project) do
     create(:project, :public, creator_id: user.id, namespace: user.namespace)

spec/requests/api/v3/issues_spec.rb

 require 'spec_helper'
 
-describe API::V3::Issues do
-  include EmailHelpers
-
+describe API::V3::Issues, :mailer do
   let(:user)        { create(:user) }
   let(:user2)       { create(:user) }
   let(:non_member)  { create(:user) }

spec/services/issues/update_service_spec.rb

 # coding: utf-8
 require 'spec_helper'
 
-describe Issues::UpdateService do
-  include EmailHelpers
-
+describe Issues::UpdateService, :mailer do
   let(:user) { create(:user) }
   let(:user2) { create(:user) }
   let(:user3) { create(:user) }

spec/services/merge_requests/update_service_spec.rb

 require 'spec_helper'
 
-describe MergeRequests::UpdateService do
-  include EmailHelpers
-
+describe MergeRequests::UpdateService, :mailer do
   let(:project) { create(:project, :repository) }
   let(:user) { create(:user) }
   let(:user2) { create(:user) }

spec/services/notification_service_spec.rb

 require 'spec_helper'
 
-describe NotificationService do
-  include EmailHelpers
-
+describe NotificationService, :mailer do
   let(:notification) { described_class.new }
   let(:assignee) { create(:user) }
 
@@ -14,7 +12,6 @@ describe NotificationService do
 
   shared_examples 'notifications for new mentions' do
     def send_notifications(*new_mentions)
-      reset_delivered_emails!
       notification.send(notification_method, mentionable, new_mentions, @u_disabled)
     end
 
@@ -137,12 +134,11 @@ describe NotificationService do
       describe '#new_note' do
         it do
           add_users_with_subscription(note.project, issue)
+          reset_delivered_emails!
 
           # Ensure create SentNotification by noteable = issue 6 times, not noteable = note
           expect(SentNotification).to receive(:record).with(issue, any_args).exactly(8).times
 
-          reset_delivered_emails!
-
           notification.new_note(note)
 
           should_email(@u_watcher)
@@ -165,9 +161,10 @@ describe NotificationService do
 
         it "emails the note author if they've opted into notifications about their activity" do
           add_users_with_subscription(note.project, issue)
-          note.author.notified_of_own_activity = true
           reset_delivered_emails!
 
+          note.author.notified_of_own_activity = true
+
           notification.new_note(note)
 
           should_email(note.author)

spec/support/notify_shared_examples.rb

@@ -7,7 +7,6 @@ shared_context 'gitlab email notification' do
   let(:new_user_address) { 'newguy@example.com' }
 
   before do
-    reset_delivered_emails!
     email = recipient.emails.create(email: "notifications@example.com")
     recipient.update_attribute(:notification_email, email.email)
     stub_incoming_email_setting(enabled: true, address: "reply+%{key}@#{Gitlab.config.gitlab.host}")

spec/support/updating_mentions_shared_examples.rb

@@ -7,8 +7,6 @@ RSpec.shared_examples 'updating mentions' do |service_class|
   end
 
   def update_mentionable(opts)
-    reset_delivered_emails!
-
     perform_enqueued_jobs do
       service_class.new(project, user, opts).execute(mentionable)
     end

spec/workers/emails_on_push_worker_spec.rb

 require 'spec_helper'
 
-describe EmailsOnPushWorker do
+describe EmailsOnPushWorker, :mailer do
   include RepoHelpers
-  include EmailHelpers
   include EmailSpec::Matchers
 
   let(:project) { create(:project, :repository) }
@@ -90,7 +89,6 @@ describe EmailsOnPushWorker do
 
     context "when there is an SMTP error" do
       before do
-        reset_delivered_emails!
         allow(Notify).to receive(:repository_push_email).and_raise(Net::SMTPFatalError)
         allow(subject).to receive_message_chain(:logger, :info)
         perform
@@ -114,8 +112,6 @@ describe EmailsOnPushWorker do
         allow_any_instance_of(Mail::TestMailer).to receive(:deliver!).and_wrap_original do |original, mail|
           original.call(Mail.new(mail.encoded))
         end
-
-        reset_delivered_emails!
       end
 
       it "sends the mail to each of the recipients" do

spec/workers/pipeline_notification_worker_spec.rb

 require 'spec_helper'
 
-describe PipelineNotificationWorker do
-  include EmailHelpers
-
+describe PipelineNotificationWorker, :mailer do
   let(:pipeline) { create(:ci_pipeline) }
 
   describe '#execute' do