Current workflow's DeepVariant is not pangenome-aware

[mr-eyes]

Hi, thanks for this super modular workflow!

Looking at `workflows/giraffe_and_deepvariant.wdl and the imported tasks/deepvariant.wdl I found that it uses the standard deepvariant not the pangenome-aware one.

vg_wdl/tasks/deepvariant.wdl

Line 22 in e230f8c

String in_dv_container = "google/deepvariant:1.8.0"

vg_wdl/tasks/deepvariant.wdl

Line 234 in e230f8c

String in_dv_gpu_container = "google/deepvariant:1.8.0-gpu"

I am not sure if this is intentional, but the pangenome-aware is at google/deepvariant:pangenome_aware_deepvariant-1.8.0 and google/deepvariant:pangenome_aware_deepvariant-1.8.0-gpu

Thanks,
—Mo