fix dropdown content throughout website

[MathewBiddle]

TODO - fix dropdown content. for some reason it is being repeated and the numerical bullets aren't working as expected.

Otherwise, everything else has been ported into the new carpentries workbench format.

Originally posted by @MathewBiddle in #139

[MathewBiddle]

Nested content in a dropdown block get's really funky. See the Examples under https://ioos.github.io/bio_mobilization_workshop/03-data-cleaning.html#getting-your-dates-in-order.

Need to do some trial and error to make sense of it all.

[MathewBiddle]

Testing at https://mathewbiddle.github.io/bio_mobilization_workshop/03-data-cleaning.html#examples

Seems to be working better. I've adjusted the organization to present the thing to be converted as a numerical list, then you can tab between the Python or R solution. The tabs are "grouped" so when you switch to R, all the tabs switch to R.

I'll fix it up a little and start working on the next examples section

[MathewBiddle]

This was never rolled into the 2025 edition of the materials. I'd like to stamp a DOI for this year's materials, then tinker with these dropdowns.