Allow state to update the gid

pillar.example

     fullname: A User
 
   ## Full list of pillar values
+  allow_gid_change: False
   buser:
     fullname: B User
     password: $6$w.............
     workphone: "(555) 555-5555"
     homephone: "(555) 555-5551"
     manage_vimrc: False
+    allow_gid_change: True
     manage_bashrc: False
     manage_profile: False
     expire: 16426

users/defaults.yaml

 users-formula:
   use_vim_formula: False
 
+users:
+  allow_gid_change: True
+

users/init.sls

     {% if not user.get('unique', True) %}
     - unique: False
     {% endif %}
+    {%- if grains['saltversioninfo'] >= [2018, 3, 1] %}
+    - allow_gid_change: {{ users.allow_gid_change if 'allow_gid_change' not in user else user['allow_gid_change'] }}
+    {%- endif %}
     {% if 'expire' in user -%}
         {% if grains['kernel'].endswith('BSD') and
             user['expire'] < 157766400 %}