Disable guest plugin loading in VIM

Following the work previously done in [1] and [2] to deactivate
guest-related services in VIM, since they were no longer being utilized
and causing coredump issues in the platform, this commit changes the
default value for the `guest_plugin_disable` config variable so
that Puppet won't reinforce the guest plugin loading in VIM.

As reported in [3], loading this plugin while having some of its
services deactivated (or functionalities removed) has proven to be
a problem when stx-openstack is applied, as both nova-compute service
and hypervisor are caught in an enable/disable loop indefinitely after
the first host lock/unlock with the application applied.

[1] https://review.opendev.org/c/starlingx/nfv/+/869817
[2] https://review.opendev.org/c/starlingx/nfv/+/870538
[3] https://bugs.launchpad.net/starlingx/+bug/2015088

Test Plan (on AIO-SX):
PASS - Build puppet-nfv package
PASS - Build and install ISO
PASS - Upload and apply stx-openstack
PASS - Verify that the `guest_plugin_disable` configuration variable
       remains `True` after the application is applied:
       $ grep 'guest_plugin_disable' /etc/nfv/vim/config.ini
PASS - Lock and unlock controller-0
PASS - Verify that both nova-compute service and hypervisor are no
       longer intermittent after the unlock

Closes-Bug: 2015088

Signed-off-by: Luan Nunes Utimura <LuanNunes.Utimura@windriver.com>
Change-Id: Iaebc8cc37eabe7b2b685622a5772544b4bce21dc

modules/puppet-nfv/src/nfv/manifests/vim.pp

@@ -24,7 +24,7 @@ class nfv::vim (
   $block_storage_plugin_disabled = false,
   $compute_plugin_disabled  = false,
   $network_plugin_disabled  = false,
-  $guest_plugin_disabled    = false,
+  $guest_plugin_disabled    = true,
   $fault_mgmt_plugin_disabled = false,
   $fault_management_pod_disabled = true,
   $vim_rpc_ip               = '127.0.0.1',