feat(testing): support to test web components

[aralroca]

Fixes #144

I have added support for testing web components, and I have also solved the problem of testing i18n translations by passing the "locale" option to the render. Also as an extra I have added the matcher toHaveElementByNodeName and the cleanup, necessary to clean the document.

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Test Web Components after rendering

You can also test Web Components after rendering them. For example, you can test a custom element:

import { render, userEvent } from "brisa/test";
import { test, expect } from "bun:test";

test("web component", async () => {
  const { container } = await render(<custom-counter />);
  const counter = container.querySelector("custom-counter")!.shadowRoot!;
  const [increment, decrement] = counter.querySelectorAll("button");

  expect(counter).toContainTextContent("0");

  userEvent.click(increment);

  expect(counter).toContainTextContent("1");

  userEvent.click(decrement);

  expect(counter).toContainTextContent("0");
});

Tip

You can use the shadowRoot property to access the shadow DOM of a custom element.