[REF] mail: RtcInvitations, review and simplify scss

Part of the overall v16 SCSS optimization/restyle, task-2704984

task-2855524

closes odoo/odoo#91536

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

addons/mail/static/src/components/rtc_invitations/rtc_invitations.scss

@@ -3,11 +3,5 @@
 // ------------------------------------------------------------------
 
 .o_RtcInvitations {
-    display: flex;
-    flex-direction: column;
-    position: absolute;
-    top: 0px;
-    right: 0px;
-    padding: map-get($spacers, 2);
     z-index: $zindex-modal;
 }

addons/mail/static/src/components/rtc_invitations/rtc_invitations.xml

@@ -2,7 +2,7 @@
 <templates xml:space="preserve">
 
     <t t-name="mail.RtcInvitations" owl="1">
-        <div class="o_RtcInvitations" t-attf-class="{{ className }}" t-ref="root">
+        <div class="o_RtcInvitations position-absolute top-0 end-0 d-flex flex-column p-2" t-attf-class="{{ className }}" t-ref="root">
             <t t-if="messaging.ringingThreads">
                 <t t-foreach="messaging.rtcInvitationCards" t-as="rtcInvitationCard" t-key="rtcInvitationCard.localId">
                     <RtcInvitationCard record="rtcInvitationCard"/>