scGPT integration-based label transfer

`workflows/annotation/scgpt_integration_knn` was deprecated in OP 2.1.0 because:

- zero-shot models are trained on gene names
- gene names are not unique, causing issues when the query and reference dataset are concatenated
- current sanitation of --var_gene_name params is tailored towards ensembl id sanitation, but results in faulty behavior when gene names are provided
