Broken tagging method with transcriptomics/tutorials/ref-based

**Tutorial steps:** https://training.galaxyproject.org/topics/transcriptomics/tutorials/ref-based/tutorial.html#analysis-of-the-differential-gene-expression **but specifically here** https://training.galaxyproject.org/topics/transcriptomics/tutorials/ref-based/tutorial.html#hands-on-add-tags-to-your-collection-for-each-of-these-factors

**Workflow:** https://training.galaxyproject.org/training-material/topics/transcriptomics/tutorials/ref-based/workflows/deg-analysis.html

**Issue:** The regular expression to parse the featurecounts file names into group tags in the list collection is not specific enough. The workflow breaks at DESeq2 early on and the hands-on doesn't have the correct instructions as a reference/check.

Example run with the error: https://usegalaxy.org/workflows/invocations/b51be7053d255f2e

Split `https://zenodo.org/record/6457007/files/GSM461176_untreat_single_featureCounts.counts`

Current (breaks workflow)
“Find pattern”: `(.*)_(.*)_(.*)`
“Replace with”: `\1_\2_\3\tgroup:\2\tgroup:\3`

Change to
“Find pattern”: `(.*)_(.*)_(.*)_(.*)`
“Replace with”:` \1_\2_\3_\4\tgroup:\2\tgroup:\3`

Leaving the workflow with the "error" as a teaching tool and only correcting the hands-on seems Ok but the correct instructions should be somewhere, yes? I'm guessing the zenodo file names had the extra _FeatureCounts added last year in the update but the instructions weren't adjusted to match.

Thanks! If this came up already, please close.

Start with the ref-based transcriptomics tutorial's “Add tags to your collection” section and the linked DEG analysis workflow, then compare their tagging instructions with the Zenodo featureCounts filename example. Update the referenced instructions so the grouping matches the filenames and verify that the workflow no longer fails at DESeq2.

Written by the indexing model from the issue text.