Proto: one cycle = one day

This MR updates the following protocol constants for mainnet:

• blocks_per_cycle from 30720 to 10800 (~1 day)
• cycles_per_voting_period from 5 to 14 (~14 days)

for ghostnet:

• blocks_per_cycle to 10800 (~12 hours)

Manually testing the MR

rely on CI

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
• Select suitable reviewers using the Reviewers field below.
• Select as Assignee the next person who should take action on that MR