Albchu/conditional settings string check

[albchu]

What are you adding in this PR?

What's next? Any followup issues?

What did you learn?

Before you deploy

• [ ] This PR includes a new checks or changes the configuration of a check
  • [ ] I included a minor bump changeset
  • [ ] It's in the allChecks array in src/checks/index.ts
  • [ ] I ran yarn build and committed the updated configuration files
    • [ ] If applicable, I've updated the theme-app-extension.yml config
  • [ ] I've made a PR to update the shopify.dev theme check docs if applicable (link PR here).

• [ ] I included a minor bump changeset
• [ ] My feature is backward compatible

• [ ] I included a patch bump changeset