Add primary group in the first user module doc example

library/system/user

@@ -181,7 +181,7 @@ options:
 
 EXAMPLES = '''
 # Add the user 'johnd' with a specific uid and a primary group of 'admin'
-- user: name=johnd comment="John Doe" uid=1040
+- user: name=johnd comment="John Doe" uid=1040 group=admin
 
 # Add the user 'james' with a bash shell, appending the group 'admins' and 'developers' to the user's groups
 - user: name=james shell=/bin/bash groups=admins,developers append=yes