Resilient embedded snippet styling
## Description
(Identified in [this comment](https://gitlab.com/gitlab-org/gitlab/-/issues/207934#note_345999881), thanks @polettix!)
Our docs site has some embedded snippets, but these snippets conflict with the docs stylesheet:

## Proposal
Let's make our embedded snippets resilient by doing style resets (such as resetting `padding`) for the elements.
issue