Nova bootstrap job efficiency

This PS attempts to make the Nova bootstrap job a little speedier.
It's been noticed that flavor check/creation on initial deployment
are rather slow, so this backgrounds the creation of each flavor,
so that the defined flavors can be checked/create in parallel,
rather than one at a time. Waits for the jobs to finish at the end.

Change-Id: Ib9ab345e5aee697a41414e927910335dd286072f

nova/Chart.yaml

@@ -14,7 +14,7 @@ apiVersion: v1
 appVersion: v1.0.0
 description: OpenStack-Helm Nova
 name: nova
-version: 0.2.11
+version: 0.2.12
 home: https://docs.openstack.org/nova/latest/
 icon: https://www.openstack.org/themes/openstack/images/project-mascots/Nova/OpenStack_Project_Nova_vertical.png
 sources:

nova/templates/bin/_bootstrap.sh.tpl

@@ -23,6 +23,7 @@ export HOME=/tmp
 # longer treated specially. Though the same behavior can be achieved w/o specifying
 #--id flag.
 # https://review.opendev.org/c/openstack/python-openstackclient/+/750151
+{
   openstack flavor show {{ .name }} || \
    openstack flavor create {{ .name }} \
 {{ if .id }} \
@@ -31,7 +32,9 @@ openstack flavor show {{ .name }} || \
    --ram {{ .ram }} \
    --disk {{ .disk }} \
    --vcpus {{ .vcpus }}
+} &
 {{ end }}
+wait
 {{ end }}
 
 {{ if .Values.bootstrap.wait_for_computes.enabled }}

releasenotes/notes/nova.yaml

@@ -32,4 +32,5 @@ nova:
   - 0.2.9 Add image clean up to rally test
   - 0.2.10 Add tls cert mounting to nova-novnc
   - 0.2.11 Add Victoria and Wallaby releases support
+  - 0.2.12 Bootstrap flavor creation efficiencies
 ...