Upgrade tests to Xcode 11.3.1

[hramos]

Summary:
Upgrade Sandcastle and Circle CI tests to use Xcode 11.4.0 across the board.

Changelog:
[Internal] - Use Xcode 11.4.0 in tests

Differential Revision: D20821844

[pull-bot]

	Messages
📖	📋 Missing Changelog - Can you add a Changelog? To do so, add a "## Changelog" section to your PR description. A changelog entry has the following format: [CATEGORY] [TYPE] - Message. CATEGORY may be: General iOS Android JavaScript Internal (for changes that do not need to be called out in the release notes) TYPE may be: Added, for new features. Changed, for changes in existing functionality. Deprecated, for soon-to-be removed features. Removed, for now removed features. Fixed, for any bug fixes. Security, in case of vulnerabilities. MESSAGE may answer "what and why" on a feature level. Use this to briefly tell React Native users about notable changes.
📖	📋 Missing Test Plan - Can you add a Test Plan? To do so, add a "## Test Plan" section to your PR description. A Test Plan lets us know how these changes were tested.
📖	📋 Missing Summary - Can you add a Summary? To do so, add a "## Summary" section to your PR description. This is a good place to explain the motivation for making this change.

Generated by 🚫 dangerJS against b92658f

[analysis-bot]

Platform	Engine	Arch	Size (bytes)	Diff
android	hermes	arm64-v8a	6,607,336	-113
android	hermes	armeabi-v7a	6,284,178	-129
android	hermes	x86	6,948,101	-97
android	hermes	x86_64	6,878,580	-102
android	jsc	arm64-v8a	8,915,609	-112
android	jsc	armeabi-v7a	8,555,795	-129
android	jsc	x86	8,740,406	-97
android	jsc	x86_64	9,317,111	-129

Base commit: 3ed1b1f

[analysis-bot]

Platform	Engine	Arch	Size (bytes)	Diff
ios	-	universal	10,843,984	48

Base commit: 3ed1b1f

[facebook-github-bot]

This pull request has been merged in 25836bc.