Replace BS global popovers init with GlPopover

What does this MR do?

This swaps Bootstrap's global popovers init script with a wrapper around GlPopover.

Heavily inspired by prior art on tooltips: https://gitlab.com/gitlab-org/gitlab/-/tree/master/app/assets/javascripts/tooltips

Screenshots

File	Before	After
app/views/projects/pipelines/_info.html.haml
app/views/projects/commit/_signature_badge.html.haml

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• [-] Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Related to #224450 (closed)