Ensure runtime deployment versions progress consistently

[peternose]

The current consensus mechanism permits removing scheduled runtime deployments and/or replacing them with a new deployment, even if the replacement has a lower version number or the same version number but a different bundle checksum. This creates challenges for version management, as versions can go backwards or the binary checksum changes.

To address this issue, the consensus should enforce the following rules:

• Scheduled deployments must not be modified once they are defined.
• Every new deployment must have a higher version number than the preceding one.
• Disallow the removal of scheduled versions entirely and instead require to overwrite them.