Updated the Devcontainer

[lenardt-gerhardts]

I updated the Devcontainer to do the following:

• Deploy a complete Netbox stack
• Automatically pulling the latest Database dump from a server to ".devcontainer/db_backup.sql.gz"
• Automatically applying the dump file located at ".devcontainer/db_backup.sql.gz"
• Automatically making and applying migrations
• Automatically creating a superuser super:12345
• Automatically starting the Netbox server and 1 rqworker

It has greatly increased my development speed for a Plugin which had to use a System Job.