Merge #416: add scrollbar to wallet select list

ba98b83 qml: add scrollbar to wallet select list (Marnix)

Pull request description:

  This adds a scrollbar to the wallet selection list.

  Addresses #401 (review)

  ---

  ### Images

  scrollbar visible on hover/when scrolling when having more wallets than that are initially visible
  ![image](https://github.com/user-attachments/assets/6cecd990-5e20-48d7-95eb-fcf79cd368d6)

  no scrollbar when not needed:
  ![image](https://github.com/user-attachments/assets/1d9d7418-858a-4576-a1fc-c63ead211919)

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ACKs for top commit:
  pablomartin4btc:
    utACK ba98b83
  jarolrod:
    ACK ba98b83

Tree-SHA512: 1013230070913dcb2be6674b9c25acc51c49b8e603b079ca6e6802b3d6b6ce7fabca44a25bef1f641c133b75051d132200573e3d5846c59beb14bcff5edbd34c

src/qml/pages/wallet/WalletSelect.qml

@@ -69,6 +69,7 @@ Popup {
             id: listView
             interactive: true
             spacing: 2
+            ScrollBar.vertical: ScrollBar { }
             model: walletListModel
 
             delegate: WalletBadge {