[IMP] im_livechat: rename search filter

This PR rename the search filter of the session history view
from "Attendees" to "Participant" as it makes more sense in
this context.

part of task-3332872

closes odoo/odoo#126937

Signed-off-by: Alexandre Kühn (aku) <aku@odoo.com>

addons/im_livechat/views/discuss_channel_views.xml

@@ -31,7 +31,7 @@
                 <tree js_class="im_livechat.discuss_channel_list" string="History" create="false" default_order="create_date desc">
                     <field name="is_member" invisible="1"/>
                     <field name="create_date" string="Session Date"/>
-                    <field name="name" string="Attendees"/>
+                    <field name="name" string="Participant"/>
                     <field name="country_id"/>
                     <field name="duration" widget="float_time" options="{'displaySeconds': True}"/>
                     <field name="message_ids" string="# Messages"/>