fix avatar stretched on 1:1 call (#12494)

Co-authored-by: Florian Duros <florianduros@element.io>

res/css/views/toasts/_IncomingLegacyCallToast.pcss

@@ -18,6 +18,7 @@ limitations under the License.
 .mx_IncomingLegacyCallToast {
     display: flex;
     flex-direction: row;
+    align-items: flex-start;
     pointer-events: initial; /* restore pointer events so the user can accept/decline */
 
     .mx_IncomingLegacyCallToast_content {