Deprecation: Native dom helpers should not be used as globals in tests anymore

# Problem

Using native dom helpers as globals is now deprecated in our tests. Instead, we should add a new dependency to our app and import these helpers from it in any tests that need it.

We are leaning away from these anyway, due to relying on ember-cli-page-object, but there are still a couple of places where we do use them.

## Subtasks
- [ ] Install depdencency https://github.com/cibernox/ember-native-dom-helpers
- [ ] Search through our tests for usage of the `find`, `click`, `fillIn`, `visit` and other global functions in this group. Careful not to mistake them for the identically named functions provided by `ember-cli-page-object`. The culprits we need to fixed are likely used as globals, in tests, directly.
- [ ] In any module that uses them, import them using `import { visit, click, find, fillIn } from 'ember-native-dom-helpers';`

Comece revisando os arquivos de teste e a configuração do pacote; em seguida, pesquise nos testes por find, click, fillIn, visit globais e helpers relacionados. Diferencie os helpers nativos do DOM das funções de ember-cli-page-object com o mesmo nome, adicione a dependência ember-native-dom-helpers e importe os helpers nativos em todos os módulos afetados. Está concluído quando nenhum uso restante de helpers nativos depender de globals.

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