Test workflow with Bioc3.19 images

[jashapiro]

The next versions of scpcaTools docker images, following the implementation of AlexsLemonade/scpcaTools#269 and possibly AlexsLemonade/scpcaTools#270, are currently planned to use Bioconductor 3.18. This release included a number of changes, which would not necessarily be expected to have large effects, but still could, of course!

Some of the most significant changes may be to zellkonverter, which includes a new version of AnnData (0.10), which does seem to change the output format a bit. With luck, this may also address the issue we had with exporting large objects. Nothing in the release notes seems to directly address this, but the changes may be significant enough to make a difference.

[jashapiro]

This was effectively completed by #763