Add eslint-plugin-jsdoc configs?

[pdehaan]

Per biancadanforth/tracking-protection-shield-study#81 (review):

@biancadanforth says: "I don't see any issues or PRs in the upstream repo to suggest JSDOC -- Do you think it's worth making one? I'm on the fence about enforcing JSDOC for all shield study authors, though I would like to use it myself..."

Not sure if it's worth adding eslint-plugin-jsdoc ESLint plugin to this repo and trying to enforce it on all studies.
Not sure if it's too heavy weight, but we could also potentially consider a custom eslint-plugin-shield-studies plugin/config which we can use to enforce some suggested rules. This way people could extend "plugin:shield-studies/recommended" config or opt in to something like "plugin:shield-studies/jsdoc" config, if they want to use JSDoc in their study.

I filed an upstream gajus/eslint-plugin-jsdoc#51 bug to add a "plugin:jsdoc/recommended" config, which would make this slightly easier.