Set Ansible default version to 2.8

Ansible 2.6 is EOL, we should move to a more recent release that
has better support for Python 3.x and, above all, is maintained
with security and critical bug fixes.

Change-Id: I6aa80b4bc4a0c34ac919951cd940b2fc6b736bdc

playbooks/test-bifrost.yaml

@@ -111,12 +111,12 @@
       command: openstack baremetal node list
       environment:
         OS_CLOUD: bifrost
-        PATH: /usr/local/bin:{{ ansible.env.PATH }}
+        PATH: /usr/local/bin:{{ ansible_env.PATH }}
     - name: "List introspection rules using openstack client"
       command: openstack baremetal introspection rule list
       environment:
         OS_CLOUD: "{% if enable_keystone | default(false) | bool == true %}bifrost{% else %}bifrost-inspector{% endif %}"
-        PATH: /usr/local/bin:{{ ansible.env.PATH }}
+        PATH: /usr/local/bin:{{ ansible_env.PATH }}
       when: enable_inspector is defined and enable_inspector | bool
 
 - hosts: baremetal

releasenotes/notes/default-ansible2.8-e0000544b2f55b88.yaml

@@ -0,0 +1,7 @@
+---
+upgrade:
+  The default version of Ansible becomes 2.8, replacing version 2.6
+  that is EOL.
+  This version guarantees full bug fix and security patches and has
+  a better support for Python 3.x.
+

scripts/env-setup.sh

@@ -5,7 +5,7 @@ set -eu
 # NOTE(pas-ha) the above exports some useful variables like
 # $PYTHON , $PIP and $VENV depending on venv install or not
 
-ANSIBLE_PIP_VERSION=${ANSIBLE_PIP_VERSION:-${ANSIBLE_GIT_BRANCH:-stable-2.6}}
+ANSIBLE_PIP_VERSION=${ANSIBLE_PIP_VERSION:-${ANSIBLE_GIT_BRANCH:-stable-2.8}}
 
 ANSIBLE_PIP_STRING=$(${PYTHON} $(dirname $0)/ansible-pip-str.py ${ANSIBLE_PIP_VERSION})