don't use an actual keystorage in Damus test apps

Reported-by: kernelkind <kernelkind@gmail.com>
Fixes: https://github.com/damus-io/notedeck/issues/150
Signed-off-by: William Casarin <jb55@jb55.com>

src/app.rs

@@ -829,7 +829,7 @@ impl Damus {
             timelines,
             textmode: false,
             ndb: Ndb::new(data_path.as_ref().to_str().expect("db path ok"), &config).expect("ndb"),
-            account_manager: AccountManager::new(None, determine_key_storage_type()),
+            account_manager: AccountManager::new(None, KeyStorageType::None),
             frame_history: FrameHistory::default(),
             show_account_switcher: false,
             show_global_popup: true,