Init command needs updating

[doakyz]

During the prep phase, the docker run command doesn't correctly setup the initdb.sql

docker run --rm guacamole/guacamole:1.5.5 /opt/guacamole/bin/initdb.sh --postgres > initdb.sql

This leads to initdb.sql being created as

Bad database type: --postgres
USAGE: /opt/guacamole/bin/initdb.sh [--postgresql | --mysql | --sqlserver]

Updating it to --postgresql fixes the issue

docker run --rm guacamole/guacamole:1.5.5 /opt/guacamole/bin/initdb.sh --postgresql > initdb.sql

--
-- Licensed to the Apache Software Foundation (ASF) under one
-- or more contributor license agreements.  See the NOTICE file
-- distributed with this work for additional information
-- regarding copyright ownership.  The ASF licenses this file
-- to you under the Apache License, Version 2.0 (the
-- "License"); you may not use this file except in compliance
-- with the License.  You may obtain a copy of the License at
--
--   http://www.apache.org/licenses/LICENSE-2.0
--
-- Unless required by applicable law or agreed to in writing,
-- software distributed under the License is distributed on an
-- "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-- KIND, either express or implied.  See the License for the
-- specific language governing permissions and limitations
-- under the License.
--

--
-- Connection group types
--

CREATE TYPE guacamole_connection_group_type AS ENUM(
    'ORGANIZATIONAL',
    'BALANCING'
);

--
-- Entity types
--

[anshibanov]

I had same bug