Remove CBM "update" after "set-timeout" (#1091)

Closes #1090

Signed-off-by: Bun K Tan <bun.k.tan@intel.com>

source/guides/maintenance/enable-systemd-boot-menu.rst

@@ -10,7 +10,6 @@ editing kernel command line parameters, etc.
 
 To set a timeout value for the systemd-boot menu, follow these steps:
 
-
 #. Boot up |CL|.
 
 #. Log in.
@@ -20,6 +19,5 @@ To set a timeout value for the systemd-boot menu, follow these steps:
    .. code-block:: bash
       
       sudo clr-boot-manager set-timeout 20
-      sudo clr-boot-manager update
 
 #. Reboot.

source/tutorials/multi-boot/dual-boot-linux.rst

@@ -279,7 +279,6 @@ also provide a path to chain-boot GRUB.
    .. code-block:: bash	
 
       sudo clr-boot-manager set-timeout 20 --path=/mnt/clearlinux
-      sudo clr-boot-manager update --path=/mnt/clearlinux
 
 #. Add a system-boot boot entry for GRUB.
    

source/tutorials/multi-boot/dual-boot-win.rst

@@ -230,8 +230,6 @@ If you prefer not to use your BIOS to load the :guilabel:`Boot Menu` and select
 
       sudo clr-boot-manager set-timeout 20 --path=/mnt/clearlinux
 
-      sudo clr-boot-manager update --path=/mnt/clearlinux
-
 #. Umount all partitions.
 
    .. code-block:: bash