API: remove get_detection_map
API: remove get_detection_map

The detection map (required for e.g. EvalRoc) should be calculated like all the other results, e.g. in the `make_snr_map` function for « classic » algorithms, or `run` for algorithms like Andromeda.

carlgogo/vip_exoplanets,henry-ngo/VIP,vortex-exoplanet/VIP