fix: only support http/https protocol in the dapp browser

[XinyuCRO]

Background: https://www.cybersecurity-help.cz/vdb/SB2023091322

Solutions from: https://github.com/electron/electron/issues/1378#issuecomment-265207386

• Only allow HTTP and HTTPS protocol, and block others
• isValidURL is a method copied from src folder, seems no way to share code between main and renderer process, so just make a simple duplication here