qt: SwapServerDialog: resize server list with dialog

Waste less space in the dialog by limiting the stretch to 10px and
resize the servers_list with the dialog by setting stretch=1 so it can
be made larger.

Fixes https://github.com/spesmilo/electrum/issues/10519

electrum/gui/qt/swap_dialog.py

@@ -534,8 +534,8 @@ class SwapServerDialog(WindowModalDialog, QtEventListener):
         vbox = QVBoxLayout()
         self.setLayout(vbox)
         vbox.addWidget(WWLabel(msg))
-        vbox.addWidget(self.servers_list)
-        vbox.addStretch()
+        vbox.addWidget(self.servers_list, stretch=1)
+        vbox.addSpacing(10)
         self.ok_button = OkButton(self)
         vbox.addLayout(Buttons(CancelButton(self), self.ok_button))
         self.setMinimumWidth(650)