T2T - Classification grid dies due to no cached column

[davmlaw]

Split off from T2T issue #814

To recreate view classifications listing grid page

Dies with :

    No cached column for genome build T2T-CHM13v2.0

See: https://app.rollbar.com/a/jimmy.andrews/fix/item/VariantGrid/5585??utm_source=rollbar-notification

Long term, the fix is SACGF/variantgrid_private#2253

However that is risky. I think we should just use GRCh38 one and label it as such in the T2T build (maybe with a hover warning)

I think there may already be a warning, via c_hgvs.is_desired_build