Pin assignment may fail when reconnecting

[wonkoderverstaendige]

When forcefully removing Arduino and then reconnecting to it, some pins have not been removed/added properly.

Traceback (most recent call last):
  File "./ui\TabSerial.py", line 103, in toggle_connection
    self.parent.update_all_tabs()
  File "C:/Users/Ronny/Documents/GitHub/Spotter/spotterQt.py", line 318, in update_all_tabs
    t.update()
  File "./ui\TabObjects.py", line 60, in update
    self.refresh_slot_table()
  File "./ui\TabObjects.py", line 209, in refresh_slot_table
    pin_idx = pins.index(slot.pin)
ValueError: <arduino.Pin object at 0x055A3E70> is not in list