remove non-functional command

Author: DaanHoogland

source/upgrading/upgrade/upgrade-4.11.rst

@@ -303,7 +303,6 @@ For KVM hosts, upgrade the ``cloudstack-agent`` package
    .. parsed-literal::
 
       $ sudo yum install -y epel-release
-      $ sudo yum install -y python36-libvirt
       $ sudo yum upgrade cloudstack-agent
 
 #. Restart the agent:

source/upgrading/upgrade/upgrade-4.13.rst

@@ -282,7 +282,6 @@ For KVM hosts, upgrade the ``cloudstack-agent`` package
    .. parsed-literal::
 
       $ sudo yum install -y epel-release
-      $ sudo yum install -y python36-libvirt
       $ sudo yum upgrade cloudstack-agent
 
 #. Restart the agent:

source/upgrading/upgrade/upgrade-4.14.rst

@@ -276,7 +276,6 @@ For KVM hosts, upgrade the ``cloudstack-agent`` package
    .. parsed-literal::
 
       $ sudo yum install -y epel-release
-      $ sudo yum install -y python36-libvirt
       $ sudo yum upgrade cloudstack-agent
 
 #. Restart the agent:

source/upgrading/upgrade/upgrade-4.15.rst

@@ -277,7 +277,6 @@ For KVM hosts, upgrade the ``cloudstack-agent`` package
    .. parsed-literal::
 
       $ sudo yum install -y epel-release
-      $ sudo yum install -y python36-libvirt
       $ sudo yum upgrade cloudstack-agent
 
 #. Restart the agent:

source/upgrading/upgrade/upgrade-4.16.rst

@@ -277,7 +277,6 @@ For KVM hosts, upgrade the ``cloudstack-agent`` package
    .. parsed-literal::
 
       $ sudo yum install -y epel-release
-      $ sudo yum install -y python36-libvirt
       $ sudo yum upgrade cloudstack-agent
 
 #. Restart the agent:

source/upgrading/upgrade/upgrade-4.17.rst

@@ -272,7 +272,6 @@ For KVM hosts, upgrade the ``cloudstack-agent`` package
    .. parsed-literal::
 
       $ sudo yum install -y epel-release
-      $ sudo yum install -y python36-libvirt
       $ sudo yum upgrade cloudstack-agent
 
 #. Restart the agent:

source/upgrading/upgrade/upgrade-4.9.rst

@@ -384,7 +384,6 @@ For KVM hosts, upgrade the ``cloudstack-agent`` package
    .. parsed-literal::
 
       $ sudo yum install -y epel-release
-      $ sudo yum install -y python36-libvirt
       $ sudo yum upgrade cloudstack-agent
 
 #. Verify that the file ``/etc/cloudstack/agent/environment.properties`` has a