treewide: drop unused imports

Signed-off-by: Bastian Krause <bst@pengutronix.de>

Author: Bastian-Krause

labgrid/driver/httpvideodriver.py

@@ -1,6 +1,6 @@
 # pylint: disable=no-member
 import subprocess
-from urllib.parse import urlsplit, urlunsplit
+from urllib.parse import urlsplit
 
 import attr
 

labgrid/driver/shelldriver.py

@@ -4,7 +4,6 @@
 import io
 import logging
 import re
-import time
 import shlex
 import ipaddress
 

labgrid/remote/client.py

@@ -2,7 +2,6 @@
 coordinator, acquire a place and interact with the connected resources"""
 import argparse
 import asyncio
-import atexit
 import contextlib
 import enum
 import os