pylint: Fix deprecated-class

There is no actual usage of deprecated classes for Python3.
Pylint complains about such for Python2. Since Python2 is no
longer supported these imports were removed.

Fixes: https://pagure.io/freeipa/issue/9117
Signed-off-by: Stanislav Levin <slev@altlinux.org>
Reviewed-By: Rob Crittenden <rcritten@redhat.com>

ipalib/plugable.py

@@ -25,6 +25,7 @@ you are unfamiliar with this Python feature, see
 http://docs.python.org/ref/sequence-types.html
 """
 
+from collections.abc import Mapping
 import logging
 import operator
 import re
@@ -51,13 +52,6 @@ from ipapython.ipa_log_manager import (
     LOGGING_FORMAT_STDERR)
 from ipapython.version import VERSION, API_VERSION, DEFAULT_PLUGINS
 
-# pylint: disable=no-name-in-module, import-error
-if six.PY3:
-    from collections.abc import Mapping
-else:
-    from collections import Mapping
-# pylint: enable=no-name-in-module, import-error
-
 if six.PY3:
     unicode = str