QM driver remaining issues for first 0.2 release

[stavros11]

https://github.com/qiboteam/qibolab/pull/933#issuecomment-2272105877

• [ ] Baking: support for durations that are not multiple of 4ns. Now we also need to handle the case of non-integer durations, potentially by casting to int and raising a warning.

• [ ] Unrolling: unroll_sequences now needs to be called by the driver.

• [ ] Parallel sweeps: the sweeper structure in the driver is updated with this in mind, however I did not fully implement it for the case len(parallel_sweepers) > 1 mainly because there is no qibocal routine using this. We may end up needing it for all routines if we drop sweeper types (#540).