Make cluster removal fail softly

VM destruction ("vagrant destroy") failed in case RKE cluster had not
been set up properly.

Initial intention for this trigger was to leave Control and Worker VMs
provisioned even if Operator VM is destroyed.

Issue-ID: ONAPARC-551
Change-Id: I2b47c539e2517a7c72675924731a0186d1ae25c0
Signed-off-by: Pawel Wieczorek <p.wieczorek2@samsung.com>
diff --git a/bootstrap/vagrant-minimal-onap/Vagrantfile b/bootstrap/vagrant-minimal-onap/Vagrantfile
index e3b2c95..3ffa6a3 100644
--- a/bootstrap/vagrant-minimal-onap/Vagrantfile
+++ b/bootstrap/vagrant-minimal-onap/Vagrantfile
@@ -149,7 +149,7 @@
 SCRIPT
 
 $rke_up = "rke up"
-$rke_down = "rke remove --force"
+$rke_down = "rke remove --force || true" # best effort
 
 $get_oom = <<-SCRIPT
   BRANCH="${1:-5.0.1-ONAP}"