chore: metadata schema validation

[castastrophe]

Description

Adds schema validation for the metadata.json assets.

How and where has this been tested?

Please tag yourself on the tests you've marked complete to confirm the tests have been run by someone other than the author.

Validation steps

Add an invalid entry to components/accordion/metadata/metadata.json:

• [x] (@pfulton) Expect yarn validator accordion to output:

components/accordion/metadata/metadata.json invalid
[
  {
    keyword: 'additionalProperties',
    dataPath: '',
    schemaPath: '#/additionalProperties',
    params: { additionalProperty: 'foo' },
    message: 'should NOT have additional properties'
  }
]

Regression testing

Validate:

1. The documentation pages for at least two other components are still loading, including:

• [ ] The pages render correctly, are accessible, and are responsive.

2. If components have been modified, VRTs have been run on this branch:

• [ ] VRTs have been run and looked at.
• [ ] Any VRT changes have been accepted (by reviewer and/or PR author), or there are no changes.

To-do list

• [x] I have read the contribution guidelines.
• [x] ✨ This pull request is ready to merge. ✨

[changeset-bot[bot]]

⚠️ No Changeset found

Latest commit: 99871f95b03e2f828a622c618cfd6888be398041

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[github-actions[bot]]

🚀 Deployed on https://pr-3059--spectrum-css.netlify.app

[github-actions[bot]]

File metrics

Summary

Total size: 4.10 MB^*

🎉 No changes detected in any packages

• Size determined by adding together the size of the main file for all packages in the library.
  
• Results are not gzipped or minified.
  
• An ASCII character in UTF-8 is 8 bits or 1 byte.