Mailchimp syntax fix

roles/mailchimpLastlogin/tasks/main.yml

@@ -21,7 +21,7 @@
   pip:
     virtualenv: "{{ install_path }}"
     name: "git+https://gitlab.erc.monash.edu.au/hpc-team/mclastlogin.git"
-    extra_args: "--update"
+    extra_args: "--upgrade"
   become: true
   become_user: "{{ cron_user }}"