Show confirmation modal before deleting account

app/assets/javascripts/lib/utils/csrf.js

...ripts/profile/account/components/delete_account_modal.vue

app/assets/javascripts/profile/account/index.js

app/assets/javascripts/repo/components/repo.vue

...assets/javascripts/vue_shared/components/popup_dialog.vue

app/assets/stylesheets/framework/modal.scss

app/assets/stylesheets/framework/variables.scss

app/controllers/registrations_controller.rb

app/models/user.rb

app/views/profiles/accounts/show.html.haml

changelogs/unreleased/winh-delete-account-modal.yml

config/webpack.config.js

spec/controllers/registrations_controller_spec.rb

spec/features/issues/issue_detail_spec.rb

spec/features/profile_spec.rb

...s/profile/account/components/delete_account_modal_spec.js

spec/models/user_spec.rb