Retire slide deck for ScanPy PBMC?

Hi, the [introduction slides with the video transcripts](https://training.galaxyproject.org/training-material/topics/transcriptomics/tutorials/scrna-intro/slides.html) were based on the [slide deck from the ScanPy PBMC tutorial](https://training.galaxyproject.org/training-material/topics/transcriptomics/tutorials/scrna-scanpy-pbmc3k/slides.html) and contain pretty much the exact same content.

Should we retire the ScanPy slide deck, and I instead make timestamped links to the introduction video within the ScanPy tutorial? (related to https://github.com/galaxyproject/training-material/pull/2474)

Or should we keep the slide deck as some kind of quick reference directly associated with the tutorial?

@nomadscientist @beatrizserrano @pavanvidem @gallardoalba

Compare the linked introduction slides and ScanPy PBMC slide deck, then review the related pull request #2474 for context. The issue is complete only after deciding whether to retire the duplicate deck or retain it as a quick reference, and making the corresponding tutorial-link or content update.

Written by the indexing model from the issue text.