[openscapes, workshop] Revert temporary workshop changes

[jnywong]

Context

This is a follow up to revert changes for #6370 and #6416 after the workshop has ended

Definition of Done

• Revert [openscapes] Offer just one allocation option for the workshop on a bigger machine: #6381
• Revert [openscapes] Workshop adjustments  #6430 (delete the disk and create a smaller one)
• Revert Adjust openscapes workshop hub to accomodate more people #6429

[GeorgianaElena]

I have asked for confirmation to delete all user data and change the hub password in https://2i2c.freshdesk.com/a/tickets/3579. Around a week of access after event was promised to users so I wanted to make sure it's ok before permorming any disruptive changes