Add `vCHORD` to oncoanalyser for HRD detection in targeted mode

[bounlu]

In the targeted mode, CHORD is disabled and vCHORD is used instead for HRD detection for a panel of samples. However, it's not implemented in nf-core/oncoanalyser yet. It will be great to have it here too. Thanks.

[scwatts]

Agreed, this will be implemented in oncoanalyser in due course! I'll leave the issue open until that piece of work is complete