Update with_items loops to use new-ish "loop" keyword

Ansible 2.4 and 2.5 are moving away from specialized loop functions
and the old syntax will eventually be deprecated and removed. I did
not change the with_fileglob loops because I'm not sure about their
syntax yet.

See: https://docs.ansible.com/ansible/latest/user_guide/playbooks_loops.html

roles/common/tasks/packages_Ubuntu.yml

@@ -8,7 +8,7 @@
 
 - name: Install base packages
   apt: pkg={{ item }}
-  with_items:
+  loop:
     - git
     - tmux
     - iotop
@@ -29,13 +29,13 @@
 
 - name: Security hardening (CIS Benchmark 1.0)
   apt: pkg={{ item }} state=absent purge=yes
-  with_items:
+  loop:
     - whoopsie # CIS 4.1
     - apport   # CIS 4.1
 
 - name: Remove annoying packages
   apt: pkg={{ item }} state=absent purge=yes
-  with_items:
+  loop:
     - command-not-found
     - command-not-found-data
     - python3-commandnotfound