fix(unifiedSearch): Prevent broken avatars for federated users

Signed-off-by: fenn-cs <fenn25.fn@gmail.com>

core/src/components/UnifiedSearch/SearchableList.vue

 						:wide="true"
 						@click="itemSelected(element)">
 						<template #icon>
-							<NcAvatar :user="element.user" :show-user-status="false" :hide-favorite="false" />
+							<NcAvatar v-if="element.isUser" :user="element.user" :show-user-status="false" />
+							<NcAvatar v-else
+								:is-no-user="true"
+								:display-name="element.displayName"
+								:show-user-status="false" />
 						</template>
 						{{ element.displayName }}
 					</NcButton>

core/src/views/UnifiedSearchModal.vue

 					subname: contact.emailAddresses[0] ? contact.emailAddresses[0] : '',
 					icon: '',
 					user: contact.id,
+					isUser: contact.isUser,
 				}
 			})
 		},