Resolve "GPG tooltips not working in Safari"

What does this MR do?

Fixes an issue with the bootstrap popover plugin in which <button> elements cannot receive focus in Firefox and Safari.

See:
https://github.com/twbs/bootstrap/issues/11788
https://github.com/twbs/bootstrap/pull/14156/files
https://gist.github.com/cvrebert/68659d0333a578d75372

Are there points in the code the reviewer needs to double check?

The GPG popover should work on Safari and Firefox.

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Review
  • Has been reviewed by Frontend
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together

What are the relevant issue numbers?

Closes #38385 (closed)