Additional tweaks for bootstrap5 support

btn-default -> btn-secondary
use mb-3 to add margin to bottom of input-groups
use $.modal('show') to show modals
use bi bi-trash icon (font-awesome doesn't seem to be included with bs5
data-bs-dismiss on the modal close buttons
put recheck templates in container divs
add input-group-text class to addon icons for input fields

mfa/templates/mfa_check.html

@@ -25,6 +25,7 @@
                     $("#modal-title").html("Recheck Indentity")
                     $("#modal-body").html(data["html"])
                     $("#popUpModal").modal()
+                    $("#popUpModal").modal('show')
                 }