Do not reuse QML account entry UI delegates.

Delegate recycling causes a bug when removing an account and then adding
it back: the old, stale UI for the account is reused instead of a new one.

In combination with 'alive' guard property on the UI for account entries,
this results in the account entry becoming frozen in the old stale state.
(Incorrect helath indicators, tokens that do not update and buttons that no
longer respond anymore.)

src/contents/ui/AccountsOverview.qml

@@ -34,10 +34,7 @@ Kirigami.ScrollablePage {
     ListView {
         id: mainList
         model: accounts
-        delegate:  Kirigami.DelegateRecycler {
-            width: parent ? parent.width : implicitWidth
-            sourceComponent: mainListDelegate
-        }
+        delegate: mainListDelegate
     }
 
     actions.main: Kirigami.Action {