Add handling for json linter failures created by the CMS

[coilysiren]

Description

The CMS produces json files that don't match the way prettier wants our json to be formatted. We would like to keep linting all our json files with prettier, so we need to have prettier run on the CMS output.

Why this is valuable:

Linting json files is good for collaboration ✨ The content files in may end up being high churn (and edited via both the CMS - and via clis / text editors), so its particularly useful to have linting active there.

Acceptance Criteria

• content is removed from .prettierignore
• new json files created by the CMS don't fail linting

Ideas

There's two primary avenues here:

• you lint pre-commit via some sort of hook in the CMS
• you lint post-push via a github hook

[deweydell]

I wonder if we can use github actions to run prettier on CMS PRs.