slcan interface needs some time-tweaking (Possible solution provided)

### Describe the bug
Messages are truncated while using send command.
Messages are truncated while using close command.

### To Reproduce
Code as example. Requires python-can and pyserial modules.
Windows PC and CANable with original firmware: https://github.com/normaldotcom/canable-fw
Counter-interface: PCAN USB dongle and oscilloscoop

Problem 1: When looping messages within the "with can.Bus", one can see on the scope that the messages are corrupted/truncated.
Problem 2: When looping messages main, one can see that the last message in the "with can.Bus" is truncated.

Possible solution:
End the _write-function with: "time.sleep(3.0e-5)"
Begin the close-function with: "time.sleep(3.0e-5)"

Additional information, experimentally obtained:
10kbps: total fail (!)
20kpbs: requires 5.0e-3 seconds
50kpbs: requires 2.0e-3 seconds
83kpbs: requires 2.0e-3 seconds
100kpbs: requires 6.0e-4 seconds
125kpbs: requires 6.0e-4 seconds
250kpbs: requires 5.0e-5 seconds
500kpbs: requires 3.0e-5 seconds
750kpbs: other side (PCAN in this case) has no setting for 750, it has 800 which is not compatible
1000kpbs: requires 4.0e-6 seconds or even lower

### Expected behavior
Truncated messages: seen on a oscilloscoop. PCAN viewer tels me stuffing errors. The error will result in resending infinite retrying messages.

### Additional context
OS and version: Windows 11
Python version: Python 3.12
python-can version: 4.3.1
pyserial version: 3.5
python-can interface/s (if applicable): slcan
Hardware interface: CANable 2.0 Pro
IDE: PyCharm recent version
Oscilloscope: Rigol DS1000-series
Counter-interface: PCAN USB isolated version and PCAN-View software

Possible solution:
End the _write-function with: "time.sleep(3.0e-5)"
Begin the close-function with: "time.sleep(3.0e-5)"

Traceback and logs

None

See code example.

```
def send_one():
with can.Bus(interface="slcan", channel="COM7@115200", bitrate=500000, sleep_after_open=0.0) as bus:
msg = can.Message(
arbitration_id=0x555, data=[0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55], is_extended_id=False
)

try:
j = 0
while j < 2:
bus.send(msg)
j = j + 1
except can.CanError:
print("Message NOT sent")

if __name__ == "__main__":
i = 0
while i < 2:
send_one()
i = i + 1
```