docs: update default server ports for Database Lab and Joe

Description

• change default values of Database Lab's and Joe's server ports:
  • Database Lab: 2345
  • Joe: 2400

Related issue

database-lab#118 (closed)

joe#145 (closed)

Checklist

• the MR description has been reviewed
• this MR contains text changes and they have been reviewed OR there are no texts changes
• this MR contains GUI/CLI changes and they have been reviewed OR there are no GUI/CLI changes
• this MR contains API changes and they have been reviewed OR there are no API changes