add 'pro config' feature

tasks/configure.yml

@@ -0,0 +1,6 @@
+---
+- name: Configure proxies & timers for 'pro' client
+  ansible.builtin.command: "pro config {{ ('set ' + item.key + '=' + item.value if item.value else 'unset ' + item.key) }}"
+  loop: "{{ ubuntu_pro_config | dict2items }}"
+  when: ubuntu_pro_config is defined
+  become: yes