Handle spike sequences correctly

[pinin4fjords]

Description of feature

Where quantification has been undertaken in the presence of technical controls (e.g ERCC spikes with RNA-seq), then this workflow should be able to handle those controls effectively.

This should involve supplying a list of technical control feature names for handling by the appropriate modules (e.g. DESeq2 for RNA-seq).

Issue for module level change required in DESeq2 is nf-core/modules#2440

[pinin4fjords]

Module-level feature added at nf-core/modules#2534