REGENIE is a C++ program for whole-genome regression modelling of large GWAS cohorts. This PR adds regenie/runl0, the module that runs one level-0 job from a split Step 1 master file produced by regenie/splitl0.

This PR depends on the regenie/splitl0 module in #11739.

PR checklist

• This comment contains a description of changes (with reason).
• If you've fixed a bug or added code that should be tested, add tests!
• If you've added a new tool - have you followed the module conventions in the contribution docs
• If necessary, include test data in your PR.
• Remove all TODO statements.
• Broadcast software version numbers to topic: versions - See version_topics
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• Use BioConda and BioContainers if possible to fulfil software requirements.
• Ensure that the test works with either Docker / Singularity. Conda CI tests can be quite flaky:
  • For modules:
    • nf-core modules test regenie/runl0 --profile docker
    • nf-core modules test regenie/runl0 --profile singularity
    • nf-core modules test regenie/runl0 --profile conda