embedding schema snippets doesn't work for some keys

`notebook` works great, `answer_histories` does not. unclear why. possibly due to `seq`? but e.g. `questions` works fine.

```
Example(s)

Answer Histories:
- answer_histories:
- label: "UseGalaxy.eu"
history: https://humancellatlas.usegalaxy.eu/u/j.jakiela/h/generating-a-single-cell-matrix-using-alevin-3
- label: "Older Alevin version"
history: https://humancellatlas.usegalaxy.eu/u/wendi.bacon.training/h/cs1pre-processing-with-alevin---answer-key
date: "2024-01-01"

```