Add latest changes from gitlab-org/gitlab@master

app/mailers/emails/profile.rb

app/mailers/previews/notify_preview.rb

app/models/concerns/has_user_type.rb

app/models/project.rb

app/services/notification_service.rb

...fy/resource_access_tokens_about_to_expire_email.html.haml

...ify/resource_access_tokens_about_to_expire_email.text.erb

app/workers/personal_access_tokens/expiring_worker.rb

doc/security/token_overview.md

locale/gitlab.pot

spec/lib/gitlab/import_export/all_models.yml

spec/mailers/emails/profile_spec.rb

spec/models/concerns/has_user_type_spec.rb

spec/models/project_spec.rb

spec/services/notification_service_spec.rb

spec/workers/personal_access_tokens/expiring_worker_spec.rb