Docs: Clean up bold/emphasis

Problem to solve

As per our styleguide, we should not be using **bold** anywhere except for UI text items: https://docs.gitlab.com/development/documentation/styleguide/#bold

This can cause slowdowns in localization as the service might be trying to figure out if the text is emphasis (should be unbolded) or UI text (bolded).

We should review our docs sets and reduce the amount of unneeded bolding throughout.

Additionally, we should also ensure that we follow the style guide when it comes to bold formatting: https://docs.gitlab.com/development/documentation/styleguide/#bold

When using bold format for UI elements or keywords, place any punctuation outside the bold tag. This rule includes periods, commas, colons, and right-angle brackets (>).

Further details

Proposal

Who can address the issue

Other links/references