Nested `<kbd>`s in docs

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

In the documentation for the latest version, in Reboot, in the user input section, the "CTRL + ," part is indicated as a single keyboard entry. In other words, it is indicated as if "+" is part of the keys the user is supposed to enter. However, we want to see CTRL + , instead of CTRL + ,

Current output:

Expected output:

Reduced test cases

We can check the issue in bootstrap documentation: https://getbootstrap.com/docs/5.3/content/reboot/#user-input

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

Windows, macOS

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

Chrome, Safari, Firefox, Microsoft Edge

What version of Bootstrap are you using?

v5.3