Populate human readable obs columns as a part of the ingest process

[mbabadi]

Human readable obs columns (e.g. cell_type, tissue) are populated from ontology columns (e.g. cell_type_ontology_term_id, tissue_ontology_term_id) by CELLxGENE Discover ingest process. We need to replicate that as a part of cellarium-cloud ingest process.

[mbabadi]

The data portal runs the following in the backend:

cellxgene-schema validate --add-labels output.h5ad input.h5ad