[Improvement] Add lesions option in bundle/stats module

[ThoumyreStanislas]

Describe your changes

Add option lesions in bundle/stats. Compute lesions stats as volume, streamlines counts.

List test packages used by your module

• tractometry.zip

Checklist before requesting a review

• Create the tool:
  • Edit ./modules/nf-scil/<category>/<tool>/main.nf
  • Edit ./modules/nf-scil/<category>/<tool>/meta.yml
• Generate the tests:
  • Edit ./tests/modules/nf-scil/<category>/<tool>/main.nf
  • Edit ./tests/modules/nf-scil/<category>/<tool>/nextflow.config
  • Add test data locally for tests with the fork repository
  • Generate the test infrastructure and md5sum for all outputs
• Ensure the syntax is correct :
  • Check indentation abides with the rest of the library (don't hesitate to correct others !)
  • Lint everything. Ensure your variables have good names.

[gagnonanthony]

LGTM 🔥

[AlexVCaron]

Everything's almost perfect, only one alignment comment, and I saw in the snapshots that the outputted bundle label_maps have the .trk stuck somewhere in the name. I can investigate to find where it happens, but I think you'll find it quicker 😁

[AlexVCaron]

@ThoumyreStanislas can you fix the last little comments when you have 2 minutes ? Then I can merge ⛵