composer update: fixed unless cmd by using -gt instead of >

(Command was not working on Ubuntu 16.04.)
Both Ubuntu's and RedHat's man pages of test list -gt, but not >
as their 'greater than' operator.

php/composer.sls

 update-composer:
   cmd.run:
     - name: "{{ install_file }} selfupdate"
-    - unless: test $(date -d "60 days $({{ install_file }} --version | cut -d ' ' -f 4,5)" "+%s") \> $(date "+%s")
+    - unless: test $(date -d "60 days $({{ install_file }} --version | cut -d ' ' -f 4,5)" "+%s") -gt $(date "+%s")
     - cwd: {{ php.local_bin }}
     - env:
       - HOME: {{ salt_user_home }}

php/ng/composer.sls

 update-composer:
   cmd.run:
     - name: "{{ install_file }} selfupdate"
-    - unless: test $(date -d "60 days $({{ install_file }} --version | cut -d ' ' -f 4,5)" "+%s") \> $(date "+%s")
+    - unless: test $(date -d "60 days $({{ install_file }} --version | cut -d ' ' -f 4,5)" "+%s") -gt $(date "+%s")
     - cwd: {{ php.lookup.pkgs.local_bin }}
     - env:
       - HOME: {{ salt_user_home }}