fix: No crash on logging out in client chooser button

lib/pages/chat_list/client_chooser_button.dart

@@ -156,7 +156,7 @@ class ClientChooserButton extends StatelessWidget {
     var clientCount = 0;
     matrix.accountBundles.forEach((key, value) => clientCount += value.length);
     return FutureBuilder<Profile>(
-      future: matrix.client.fetchOwnProfile(),
+      future: matrix.client.isLogged() ? matrix.client.fetchOwnProfile() : null,
       builder: (context, snapshot) => Material(
         clipBehavior: Clip.hardEdge,
         borderRadius: BorderRadius.circular(99),
@@ -171,7 +171,7 @@ class ClientChooserButton extends StatelessWidget {
             child: Avatar(
               mxContent: snapshot.data?.avatarUrl,
               name:
-                  snapshot.data?.displayName ?? matrix.client.userID!.localpart,
+                  snapshot.data?.displayName ?? matrix.client.userID?.localpart,
               size: 32,
             ),
           ),