CI: Remove dbus from bindep and playbooks

Change-Id: I8b4e649e24871b1191dba39d766b6c133c7e8f24

bindep.txt

-dbus [platform:dpkg]
 libffi-dev [platform:dpkg]
 libffi-devel [platform:rpm]
 gcc [platform:rpm]

tests/pre.yml

@@ -22,12 +22,6 @@
       command: python3 -m pip install -U virtualenv
       become: True
 
-    - name: Install dbus for debian system
-      apt: name=dbus
-      when:
-        - ansible_os_family == 'Debian'
-      become: true
-
     - name: Ensure /tmp/logs/ dir
       file:
         path: "{{ logs_dir }}"