Fix the test report modal

What does this MR do and why?

Fix the test report modal

This changes the width of the system output section of the test report modal for merge requests

#8254 (closed)

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

Before	After

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

1. Fork the following project https://gitlab.com/jivanvl/junit-js-tests
2. Create a failing test inside the sum.test.js file in a new branch, e.g.

test('2 is fish', () => {
  expect(2).toBe('fish');
});

3. Create a commit and a MR for that commit and wait for pipeline to fail
4. Expand the test report section and choose the failing test