`CELLRANGER_MKVDJREF` and `CELLRANGER_MULTI` failing in the tests

### Description of the bug Hi, I am encountering two errors when running the cellrangermulti test profile. 1. **`CELLRANGER_MKVDJREF` error** The first one is in the `CELLRANGER_MKVDJREF` module: ``` [error] An empty constant regions file was generated/detected for your custom species. Please check if there are hits to the IMGT database or run cellranger vdj in denovo mode without reference. ``` The issue however seems to come from the `CELLRANGER_MKGTF` module. It can be avoided by adding the following configuration: ``` process { withName: 'NFCORE_SCRNASEQ:SCRNASEQ:CELLRANGER_MULTI_ALIGN:CELLRANGER_MKGTF' { ext.args = "--attribute=gene_biotype:protein_coding --attribute=gene_biotype:IG_V_gene --attribute=gene_biotype:IG_J_gene --attribute=gene_biotype:IG_D_gene --attribute=gene_biotype:IG_C_gene --attribute=gene_biotype:TR_V_gene --attribute=gene_biotype:TR_J_gene --attribute=gene_biotype:TR_D_gene --attribute=gene_biotype:TR_C_gene" } } ``` 2. **`CELLRANGER_MULTI` error** After applying the above modification, the pipeline proceeds further but then fails in the `CELLRANGER_MULTI` module with: ``` These library types are not compatible with Flex: Multiplexing Capture ``` This appears to be related to how the FRNA probeset is added in `main.nf`. The error can be avoided by modifying the logic introduced in this commit: https://github.com/nf-core/modules/commit/2501026a8888cac0d2ddac55207a7fdae0ef1f0f Specifically, changing: ``` frna_probeset = gex_frna_probeset_name != '' ? "probe-set,./$gex_frna_probeset_name" : '' ``` to ``` frna_probeset = include_frna && gex_frna_probeset_name != '' ? "probe-set,./$gex_frna_probeset_name" : '' ``` I am not entirely sure what side effects this change might have on other use cases, or whether this behavior is expected for the `test_cellrangermulti` profile. Any guidance on this would be very helpful. ### Command used and terminal output ```console nextflow run main.nf -profile singularity,test_cellrangermulti,human --outdir results ``` ### Relevant files _No response_ ### System information _No response_