pythoncan: timeout is incorrectly multiplied by 1000

[oystub]

Description

When calling receive on a PythonCAN driver, the timeout parameter is accidentally multiplied by 1000.

pydronecan/dronecan/driver/python_can.py

Line 139 in 19ac176

timeout = -1 if timeout is None else (timeout * 1000)

This leads to the true timeout duration being 1000x too long. For example leading to dronecan_gui_tool taking over a minute to load when using python-can on a bus without traffic.

Based om the python-can driver, it should simply be passed along without changes.
https://github.com/hardbyte/python-can/blob/654a02ae24bfc50bf1bb1fad7aab4aa88763d302/can/bus.py#L110-L121

...and it seems to have been like that for at least 7 years 🤔
https://github.com/hardbyte/python-can/blob/6913c4951faba39eb9d9fea2a9f151d60a39d9e0/can/bus.py#L45-L53

Proposed solution

Remove the problematic line
See #78

To reproduce on Debian/Ubuntu:

1. Create a virtual socketcan device

sudo modprobe vcan
sudo ip link add dev vcan0 type vcan
sudo ip link set up vcan0

2. Run the following program

import time
import dronecan.driver as driver
from dronecan.node import Node

driver_pythoncan = driver.PythonCAN(bustype="socketcan", channel='vcan0', bitrate=1000000)
driver_socketcan = driver.SocketCAN(interface='vcan0', bitrate=1000000)

node = Node(driver_pythoncan)
start = time.time()
node.spin(0.01)
print(f"python-can: {time.time() - start}s")

node = Node(driver_socketcan)
start = time.time()
node.spin(0.01)
print(f"socketcan: {time.time() - start}s")

Which outputs something like

python-can: 10.00549864768982s
socketcan: 0.010323524475097656s