Odoo Release Updates

[IMP] web,*: kanban,list: use <button> tags to add records

[REF] *: switch from pytz to zoneinfo

[IMP] portal, website, *: correct title hierarchy for accessibility, SEO

[IMP] website*: remove useless invisible fields

[FIX] website_event: deal with dead "s_speaker_bio" snippet

[FIX] website_event: regex gets incorrect event id

[CLN] *: manifests

[FIX] website_*: allow registration to slots on all pages of an event

[CLN] website_*: clean the slots registration button

[FIX] website_event: translatable "Select a Date" for slots

[FIX] *: automaticaly set legacy at_install

[IMP] base: Warning on unused attributes in ir.qweb

[IMP] base,all: remove deprecated 't-esc' ir.qweb directive

[IMP] website_event: add online events option and default country

[IMP] website, *: improve publication scheduling and consistency

[IMP] html_builder, *: refine social/share icon options

[IMP] auth_totp_mail, *: remove obsolete .btn-block