Improve SDP release process and enable system integration testing

SDP integration CI pipeline has been optimised to allow it to finish as quickly as possible. - ORCA, NALEDI, YANDA skart has been adopted more thoroughly to enable us to propagate changes to SDP integration as quickly as possible: skart is further developed and its documentation updated to support wider usage - ORCA real-time processing repositories use skart - YANDA? The suite of test processing scripts has been expanded to allow the SDP to produce mock outputs in the absence of (simulated or real) signal chain inputs by writing data products to storage, - ORCA publishing Mid pointing offset calibration solutions on Tango attributes to Kafka (then QueueConnector loads from Kafka to Tango), and - ORCA (as a stretch) publishing tied-array beamformer calibration solutions on Tango attributes. A time-boxed contribution of 1 FP has been made to the system integration efforts: - ORCA, NALEDI, YANDA adding the SDP to the Low and Mid control system integration deployments, and creating and maintaining the system integration tests.