Change Amphora flavor from public to private

In octavia, when create specified nova flavor for Amphora,
it's supposed to be accessed by octavia for creating Amphora instances,
and other projetcs/users shouldn't get this flavor[1].

[1] https://github.com/openstack/octavia/blob/master/devstack/plugin.sh#L396

Closes-Bug: #1729450
Change-Id: I1d2b74dd99d949263e24b62c427c8718ec8de5b0

manifests/worker.pp

@@ -111,6 +111,7 @@ class octavia::worker (
         'ram'       => '1024',
         'disk'      => '2',
         'vcpus'     => '1',
+        'is_public' => false,
         'tag'       => ['octavia']
       }
       $nova_flavor_defaults = merge($octavia_flavor_defaults, $nova_flavor_config)

releasenotes/notes/change-amphora-flavor-property-178cb1a154af80ba.yaml

@@ -0,0 +1,3 @@
+---
+fixes:
+  - Change amphora flavor is_public property from true to false.

spec/classes/octavia_worker_spec.rb

@@ -62,6 +62,7 @@ describe 'octavia::worker' do
         :ram       => '1024',
         :disk      => '2',
         :vcpus     => '1',
+        :is_public => false,
         :tag       => ['octavia'],
       )
     end