fix metro for example app for iOS

[zibs]

Description

Fixes metro with monorepo: https://docs.expo.dev/guides/monorepos/#modify-the-metro-config

I missed with #988 when verifying it worked on iOS that I hadn't cleared my node modules before running, so all the deps worked fine. But if someone were to clone the repo from fresh and try, they'd run into metro errors.

Steps to verify

Clone the repo and follow the install and running steps and see the app work.

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
react-native-app-auth	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jul 24, 2024 4:48pm

[changeset-bot]

⚠️ No Changeset found

Latest commit: 6370cc5

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