Review twpa pump calibration

[alecandido]

Notable changes:

• the probe and acquisition performed were taken from the calibrated measurement; now, they are independent, and the probe is set to a rectangular pulse, whose amplitude and duration are exposed as parameters; the same duration is also used by the acquisition
• the TWPA pump (RF source) was disconnected in the reference, relying on the automated shutdown; this is not any longer true, since introduce turn_off_on_disconnect flag in LocalOscillator qibolab#1348; in this PR, it has been replaced by an explicit shutdown