[REM] im_support: remove im_support module

The goal of the module was to communicate with livechat operators on our
production server, except the feature is disabled on our prod and we don't plan
to reactivate it any time soon.

closes odoo/odoo#52691

Related: odoo/upgrade#1313
Signed-off-by: Christophe Simonis <chs@odoo.com>

.github/CODEOWNERS

@@ -46,9 +46,6 @@
 
 /addons/im_livechat/ @odoo/rd-discuss @odoo/rd-sm
 
-/addons/im_support/ @odoo/rd-discuss
-/addons/im_support/models/ir_http.py @odoo/rd-discuss @odoo/rd-website
-
 /addons/mail/ @odoo/rd-discuss
 /addons/mail/**/*.py @odoo/rd-discuss @odoo/rd-sm
 /addons/mail/models/ir_http.py @odoo/rd-discuss @odoo/rd-sm @odoo/rd-website