Fix bootstrap.yml in Bifrost

The bootstrap.yml playbook attempts to source
/opt/stack/ansible/hacking/env-setup and fails because no such file
exists (ansible is not installed in the location /opt/stack/). This step
is not required since the command bash ./scripts/env-setup.sh does not
install ansible from source in the Bifrost container as ansible is
already installed in the base image used by the Bifrost container.

Change-Id: Ibc26b4b77866127e7b57a30d80cd15734dedd85d
Closes-Bug: #1658741

ansible/roles/bifrost/tasks/bootstrap.yml

@@ -3,8 +3,7 @@
   command: >
      docker exec bifrost_deploy
      bash -c '/bifrost/scripts/env-setup.sh && source /bifrost/env-vars
-     && source /opt/stack/ansible/hacking/env-setup &&
-     ansible-playbook -vvvv -i /bifrost/playbooks/inventory/localhost
+     && ansible-playbook -vvvv -i /bifrost/playbooks/inventory/localhost
      /bifrost/playbooks/install.yaml -e @/etc/bifrost/bifrost.yml
      -e @/etc/bifrost/dib.yml -e  skip_package_install=true'
 - name: Installing ssh keys