fix agenda modal not showing

Created by: flora8984461

According to the NOTE in https://eclipsefdn-hugo-solstice-theme.netlify.app/components/agenda/, you need to add {{< bootstrap/modal id=“eclipsefdn-modal-event-session” >}} in order to enable the modal of abstract in Agenda.

@phkrief Please check this small arrow near the third agenda item.

Thanks!

Signed-off-by: Yi Liu yi.liu@eclipse-foundation.org