chore: update Etherpad

[pedrobmarin]

Following https://github.com/bigbluebutton/bigbluebutton/pull/14550 .

Also updated the settings.json file with https://github.com/ether/etherpad-lite/blob/1.8.17/settings.json.template .

Made sure to preserve BigBlueButton's common settings and a couple of extras that I imagined to make sense for the docker environment:

• ip: 0.0.0.0 BigBlueButton uses 127.0.0.1

  /*
  * IP and port which Etherpad should bind at.
  *
  * Binding to a Unix socket is also supported: just use an empty string for
  * the ip, and put the full path to the socket in the port parameter.
  *
  * EXAMPLE USING UNIX SOCKET:
  *    "ip": "",                             // <-- has to be an empty string
  *    "port" : "/somepath/etherpad.socket", // <-- path to a Unix socket
  */
  "ip": "0.0.0.0",
  "port": 9001,

• host: redis BigBlueButton uses 127.0.0.1

  /*
  * The type of the database.
  *
  * You can choose between many DB drivers, for example: dirty, postgres,
  * sqlite, mysql.
  *
  * You shouldn't use "dirty" for for anything else than testing or
  * development.
  *
  *
  * Database specific settings are dependent on dbType, and go in dbSettings.
  * Remember that since Etherpad 1.6.0 you can also store this information in
  * credentials.json.
  *
  * For a complete list of the supported drivers, please refer to:
  * https://www.npmjs.com/package/ueberdb2
  */
  
  "dbType": "redis",
  "dbSettings": {
  "host": "redis",
  "port": 6379
  },

• soffice: /etherpad-export.sh BigBlueButton uses /usr/share/bbb-libreoffice-conversion/etherpad-export.sh

  /*
  * This is the absolute path to the soffice executable.
  *
  * LibreOffice can be used in lieu of Abiword to export pads.
  * Setting it to null disables LibreOffice exporting.
  */
  "soffice": "/etherpad-export.sh",

• disableIPlogging: true BigBlueButton uses false (Etherpad's default)

  /*
  * Privacy: disable IP logging
  */
  "disableIPlogging": true,

• host: redis BigBlueButton uses 127.0.0.1

  /*
  * Redis publisher plugin configuration.
  * npm i git+https://git@github.com/mconf/ep_redis_publisher.git
  */
  
  "ep_redis_publisher": {
  "host": "redis",
  "port": 6379
  },

Needs to be tested :)

[alangecker]

looks good, thanks for the work :)