fix ansible warnings

defaults/main.yml

@@ -30,8 +30,8 @@ certbot_command_arguments:
 # @var certbot_cron_enabled:description: Enable scheduling via cron.
 certbot_cron_enabled: True
 
-certbot_cron_minute: 30
-certbot_cron_hour: 3
+certbot_cron_minute: "30"
+certbot_cron_hour: "3"
 
 # @var certbot_cron_file:description: Use a file under /etc/cron.d but this will only work if `certbot_user`
 # has write permissions for this location.

tasks/install.yml

@@ -33,7 +33,7 @@
         src: config/credentials.ini.j2
         dest: "{{ certbot_config_dir }}/credentials.ini"
         mode: 600
-      when: certbot_credentials
+      when: certbot_credentials | default([]) | length > 0
 
     - name: Schedule certbot run
       cron: