BUG #16756: about pg13.0 new feature--“Remove --adduser and --no-adduser from createuser”

The following bug has been logged on the website:

Bug reference:      16756
Logged by:          yanliang lei
Email address:      leiyanliang@highgo.com
PostgreSQL version: 13.0
Operating system:   CentOS7.6
Description:

in the https://www.postgresql.org/docs/release/13.0/ ，there is  following
descrption:
Remove --adduser and --no-adduser from createuser (Alexander Lakhin)

but in the pg12.1 version's createuser --help output，there is no --adduser
or --no-adduser ，I want to know why？

[pg121@iZm5ehqfjhnsbtxrzrnh2zZ ~]$ createuser --help
createuser creates a new PostgreSQL role.

Usage:
  createuser [OPTION]... [ROLENAME]

Options:
  -c, --connection-limit=N  connection limit for role (default: no limit)
  -d, --createdb            role can create new databases
  -D, --no-createdb         role cannot create databases (default)
  -e, --echo                show the commands being sent to the server
  -g, --role=ROLE           new role will be a member of this role
  -i, --inherit             role inherits privileges of roles it is a
                            member of (default)
  -I, --no-inherit          role does not inherit privileges
  -l, --login               role can login (default)
  -L, --no-login            role cannot login
  -P, --pwprompt            assign a password to new role
  -r, --createrole          role can create new roles
  -R, --no-createrole       role cannot create roles (default)
  -s, --superuser           role will be superuser
  -S, --no-superuser        role will not be superuser (default)
  -V, --version             output version information, then exit
  --interactive             prompt for missing role name and attributes
rather
                            than using defaults
  --replication             role can initiate replication
  --no-replication          role cannot initiate replication
  -?, --help                show this help, then exit

Connection options:
  -h, --host=HOSTNAME       database server host or socket directory
  -p, --port=PORT           database server port
  -U, --username=USERNAME   user name to connect as (not the one to
create)
  -w, --no-password         never prompt for password
  -W, --password            force password prompt

Report bugs to <pgsql-bugs@lists.postgresql.org>.
[pg121@iZm5ehqfjhnsbtxrzrnh2zZ ~]$