Remove hardcoded instances of `stack` from roles

We are moving away from hardcoding the stack user and opting to
replace it with `undercloud_user` and `non_root_user` as appropriate
to increase flexibility of OOOQ and OOOQ-Extras.

Change-Id: I7ea43a3fabab2c69fd4f3b5550ea5e4627443406

roles/baremetal-undercloud/tasks/machine-setup.yml

@@ -90,7 +90,7 @@
     groups: undercloud
     ansible_host: undercloud
     ansible_fqdn: undercloud
-    ansible_user: stack
+    ansible_user: "{{ undercloud_user }}"
     ansible_private_key_file: "{{ undercloud_key }}"
     ansible_ssh_extra_args: '-F "{{local_working_dir}}/ssh.config.ansible"'
     ansible_scp_extra_args: '-F "{{local_working_dir}}/ssh.config.ansible"'

roles/overcloud-upgrade/templates/major-upgrade-overcloud.sh.j2

@@ -25,7 +25,7 @@ trap onerror ERR
 # Note, tripleo-heat-templates rdo package is not up to date.
 # It simlpier to clone the stable branch instead, while waiting of the
 # latest fixes.
-rm -rf /home/stack/tripleo-heat-templates
+rm -rf "{{ working_dir }}/tripleo-heat-templates"
 git clone https://github.com/openstack/tripleo-heat-templates.git -b stable/newton
 {% endif %}
 

roles/virthost-full-cleanup/tasks/main.yml

@@ -55,7 +55,7 @@
 
     - name: destroy local libvirt storage, networks and config
       become: yes
-      shell: rm -rf /home/stack/.config/libvirt
+      shell: "rm -rf {{ working_dir }}/.config/libvirt"
 
     - name: get user_id for stack user
       shell: >
@@ -103,7 +103,6 @@
 
     - name: remove stack home dir
       shell: rm -Rf {{ item }}
-
       with_items:
         - /home/{{ non_root_user }}
         - /var/spool/mail/{{ non_root_user }}