Chore/8201 deprecate json tokens

[weronikaolejniczak]

Summary

I added a new rule to our ESLint plugin, no-restricted-eui-imports, that won't conflict with the inbuilt no-restricted-imports rule and will allow us to define several error levels at once. I.e. we want some imports to be marked as warning and not an error, as it's done in Kibana.

Context:

• Previous Kibana PR
• Slack thread

The JSON token imports in @kbn/eslint/module_migration need to be removed as well:

https://github.com/elastic/kibana/blob/212b1926743ca5821992c2877d9c68f621e1875e/packages/kbn-eslint-config/.eslintrc.js#L131-L140

QA

1. Pack the ESLint plugin: yarn workspace @elastic/eslint-plugin-eui pack
2. Go to Kibana and point the EUI ESLint plugin to the tarball: "@elastic/eslint-plugin-eui": "file:path/to/the/package.tgz"
3. Install dependencies in Kibana: yarn and bootstrap: yarn kbn bootstrap --no-validate

Unit tests: yarn workspace @elastic/eslint-plugin-eui test

[kibanamachine]

Preview staging links for this PR:

• Docs site: https://eui.elastic.co/pr_8246/
• Storybook: https://eui.elastic.co/pr_8246/storybook
• New docs: https://eui.elastic.co/pr_8246/new-docs

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: b8d7a96

History

• 💔 Build #3299 failed 6a751f9
• 💚 Build #3282 succeeded 5cd5dd5
• 💚 Build #3262 succeeded 8e894b6