Put CPU improvement in test

docs/man/glances.1

 .\" Man page generated from reStructuredText.
 .
-.TH "GLANCES" "1" "May 26, 2021" "3.1.8b3" "Glances"
+.TH "GLANCES" "1" "May 27, 2021" "3.1.8b4" "Glances"
 .SH NAME
 glances \- An eye on your system
 .

glances/__init__.py

@@ -2,7 +2,7 @@
 #
 # This file is part of Glances.
 #
-# Copyright (C) 2020 Nicolargo <nicolas@nicolargo.com>
+# Copyright (C) 2021 Nicolargo <nicolas@nicolargo.com>
 #
 # Glances is free software; you can redistribute it and/or modify
 # it under the terms of the GNU Lesser General Public License as published by
@@ -29,7 +29,7 @@ import sys
 # Global name
 # Version should start and end with a numerical char
 # See https://packaging.python.org/specifications/core-metadata/#version
-__version__ = '3.1.8b3'
+__version__ = '3.1.8b4'
 __author__ = 'Nicolas Hennion <nicolas@nicolargo.com>'
 __license__ = 'LGPLv3'