Multiome: Generate chromosome length from fasta files.

[Bento007]

currently the chromosome table for both mouse and human are hardcoded into the atac_seq.py. This will eventually become problematic when it's time to update the gencode version. This process should be automated when ever gencode version are updated.

single-cell-curation/cellxgene_schema_cli/cellxgene_schema/atac_seq.py

Lines 24 to 25 in ded6f4c

	# TODO: these chromosome tables should be calculated from the fasta file?
	# location of fasta https://www.gencodegenes.org/human/release_44.html and file name GRCh38.primary_assembly.genome.fa

DoD

The chromosome lengths are generate from a fasta file from gencode and usable by the atac validation code.