Create a named list of cell labels returned from SingleR::SingleR().
Source: R/cell_annotation.R
cell_annotation_labels_fn.RdSingleR::SingleR() returns three types of cell labels. In the returned list from this function,
names of those are prefixed by a reference dataset's name and modified such that:
first.labels("raw" labels) -><reference_name>_labels_rawlabels(fine-tuned, unpruned labels) -><reference_name>_labelspruned.labels(fine-tuned and pruned labels) -><reference_name>_labels_pruned
Pruned labels contain NAs for low quality labels.