Fix style (got tired of it)

tests/ci/pvs_check.py

@@ -2,7 +2,6 @@
 
 # pylint: disable=line-too-long
 
-import subprocess
 import os
 import json
 import logging

tests/ci/tee_popen.py

@@ -10,12 +10,14 @@ import os
 # it finishes. stderr and stdout will be redirected both to specified file and
 # stdout.
 class TeePopen:
+    # pylint: disable=W0102
     def __init__(self, command, log_file, env=os.environ.copy()):
         self.command = command
         self.log_file = log_file
         self.env = env
 
     def __enter__(self):
+        # pylint: disable=W0201
         self.process = Popen(self.command, shell=True, universal_newlines=True, env=self.env, stderr=STDOUT, stdout=PIPE, bufsize=1)
         self.log_file = open(self.log_file, 'w', encoding='utf-8')
         return self