Migrate Popper 2 to Floating UI

[PanderMusubi]

Please see https://floating-ui.com/docs/migration and migrate the files in static/bootstrap5/umd from Popper 2 to Floating UI and also where Popper 2 is used.

[PanderMusubi]

File that needs migration is https://github.com/helloflask/bootstrap-flask/blob/master/flask_bootstrap/__init__.py

[PanderMusubi]

Note, if popper is only used by Bootstrap 4, we can leave it as is and not upgrade of migrate it.

[PanderMusubi]

I think they also made a release for popper, see https://github.com/floating-ui/floating-ui/releases but first we have to see to migrate or not.