Dark Mode: Code Block in Test Report Details has bad colors

Summary

The <pre class="code-block rounded"> element in the modal window opened after clicking the View details button in CI/CD Pipeline's test report is not readable in dark theme.

Steps to reproduce

1. Swith to the Dark Mode (alpha)
2. Open any Test Report with a failed test containing some details about the failure
3. Click View details

Example Project

https://gitlab.com/himura/gitlab-test-reports/-/pipelines/322695440/test_report

What is the current bug behavior?

.code-block {
    background: #fff;
    color: #c4c4c4;
}

What is the expected correct behavior?

The code background is dark.

Relevant logs and/or screenshots

Results of GitLab environment info

Both GitLab.com and Self-hosted versions.

Possible fixes

• https://gitlab.com/gitlab-org/gitlab/-/blob/master/app/assets/stylesheets/framework/blocks.scss#L346
• https://gitlab.com/gitlab-org/gitlab/-/blob/master/app/assets/stylesheets/themes/_dark.scss#L83