Make it optional to hide offcanvas when resizing the window

Prerequisites

• I have searched for duplicate or closed feature requests
• I have read the contributing guidelines

Proposal

Hi,

When the user resizes the window, all offcanvas that are not in the fixed position are hidden because of this piece of code: https://github.com/twbs/bootstrap/blob/bada2b9a90be728da0157a6f96e4de5364035f5f/js/src/offcanvas.js#L266-L272

So I suggest to make this behavior optional, for example by creating a hideOnWindowResizing option (true by default).

Motivation and context

In some cases we don't want to hide the offcanvas on window resizing, even when the positions are absolute. In some of UI I have created, this causes problems for my users. It would be very appreciated to implement an option such this one.