Merge pull request #4351 from SomberNight/2fa_sign_then_otp

trustedcoin: sign first, then prompt for OTP

gui/qt/main_window.py

@@ -1588,8 +1588,6 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
             # can sign directly
             task = partial(Transaction.sign, tx, self.tx_external_keypairs)
         else:
-            # call hook to see if plugin needs gui interaction
-            run_hook('sign_tx', self, tx)
             task = partial(self.wallet.sign_transaction, tx, password)
         WaitingDialog(self, _('Signing transaction...'), task,
                       on_signed, on_failed)