Breaking change for v6: fix overflow scrollbar for code block in reboot

[patrickhlauke]

Prerequisites

• I have searched for duplicate or closed issues
• I have validated any HTML to avoid common problems
• I have read the contributing guidelines

Describe the issue

While #37694 fixes the immediate issues in our documentation, the problem with the overflow horizontal scrollbar covering up the last line of a code block is one that affects the rebooted code blocks in general ... see this screenshot of the docs in firefox (the code block there has been modified to force the appearance of the scrollbar)

This issue should be resolved directly at source in our reboot styles, but as this is a breaking change (since it has the potential of compounding any such local fixes developers may have applied themselves already to fix the problem in their sites), it should be deferred to the next version.

Reduced test cases

See the documentation in Firefox, Safari, Chrome/macOS, force some extra content into the code block example using developer tools https://getbootstrap.com/docs/5.3/content/reboot/#code-blocks

What operating system(s) are you seeing the problem on?

Windows

What browser(s) are you seeing the problem on?

Firefox

What version of Bootstrap are you using?

5.3