[RN][iOS] Use prebuilds in E2E tests

[cipolleschi]

Summary:

Now that we are using prebuilds by default in the release, we should also use prebuilds when running the E2E tests of the template app

Changelog:

[Internal] -

Test Plan:

GHA

[meta-codesync]

@cipolleschi has imported this pull request. If you are a Meta employee, you can view this in D90673567.

[github-actions]

Job Summary for Gradle

Test All :: run_fantom_tests

Gradle Root Project	Requested Tasks	Gradle Version	Build Outcome	Build Scan®
react-native-github	:private:react-native-fantom:buildFantomTester	9.0.0	❌

[cortinico]

Review automatically exported from Phabricator review in Meta.

[meta-codesync]

@cipolleschi merged this pull request in 7ed7540.

[react-native-bot]

This pull request was successfully merged by @cipolleschi in 7ed7540

^{When will my fix make it into a release? | How to file a pick request?}