Do not create kolla_user by default

Change-Id: I530ca17a0f2081efd08893bf8f311e1c91645ce8
Depends-On: https://review.opendev.org/c/openstack/kolla-ansible/+/855017

releasenotes/notes/not-create-user-by-default-0907eee2b6a38615.yaml

@@ -0,0 +1,5 @@
+---
+upgrade:
+  - |
+    ``create_kolla_user`` is set to ``False`` by default so that no user
+    is created as it is not used further by default.

roles/baremetal/defaults/main.yml

@@ -20,7 +20,7 @@ epel_yum_package: "epel-release"
 
 customize_etc_hosts: True
 
-create_kolla_user: True
+create_kolla_user: False
 
 kolla_user: "kolla"
 kolla_group: "kolla"

roles/docker_sdk/defaults/main.yml

@@ -26,7 +26,7 @@ virtualenv:
 # are not available on PyPI.
 virtualenv_site_packages: True
 
-create_kolla_user: True
+create_kolla_user: False
 kolla_user: "kolla"
 
 # Owner of the virtualenv.