New Data: data loader for cisTarget database

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Describe the problem
TF-target interaction is a missing opportunity as Multi-Instance Prediction.

Describe the solution you'd like
SCENIC+ / pySCENIC already has a well described resource https://resources.aertslab.org/cistarget/databases/

Additional context
This data is important several downstream tasks and inclusion of the data in TDC can be very useful.

• Badia-i-Mompel, P., et al. Gene regulatory network inference in the era of single-cell multi-omics. Nat Rev Genet (2023)

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cc @ghuls