Make it possible to find transfer user by email

The Vue Multiselect uses one prop for the local search. Although the API
already returned matching users for a given email, the users were
filtered out as their displayname doesn't contain the search string –
the email address.

Disabling the local seach and only using the most recently fetched
matches fixes this problem.

Signed-off-by: Christoph Wurst <christoph@winzerhof-wurst.at>

apps/files/src/components/TransferOwnershipDialogue.vue

@@ -53,6 +53,7 @@
 						:loading="loadingUsers"
 						track-by="user"
 						label="displayName"
+						:internal-search="false"
 						:clear-on-select="false"
 						:user-select="true"
 						@search-change="findUserDebounced" />
@@ -162,6 +163,7 @@ export default {
 					logger.error('Error fetching suggestions', { response })
 				}
 
+				this.userSuggestions = {}
 				response.data.ocs.data.users.forEach(user => {
 					Vue.set(this.userSuggestions, user.value.shareWith, {
 						uid: user.value.shareWith,