Detect Rosetta2 and fail if x86_64 is used on arm64

Running `pod install` from inside Rosetta2 can lead to problems, try
to avoid doing that by hinting users from use_react_native!() function.

   $ arch -x86_64 pod install
   Building RNTester with Fabric enabled.
   Building RNTester with Fabric enabled.
   Building RNTester with Fabric enabled.
   Analyzing dependencies
   Downloading dependencies
   Generating Pods project
   Integrating client project
   Pod installation complete! There are 63 dependencies from the Podfile and 50 total pods installed.

   [!] Do not use Rosetta2 with "pod install"

   [!] Do not use Rosetta2 with "pod install"

   [!] Do not use Rosetta2 with "pod install"

scripts/react_native_pods.rb

@@ -16,6 +16,11 @@ def use_react_native! (options={})
   # Include Hermes dependencies
   hermes_enabled = options[:hermes_enabled] ||= false
 
+  # Running `pod install` from inside Rosetta2 is a bad sign
+  if `/usr/sbin/sysctl -n hw.optional.arm64 2>&1`.to_i == 1 && !RUBY_PLATFORM.start_with?('arm64')
+    Pod::UI.warn 'Do not use Rosetta2 with "pod install"'
+  end
+
   # The Pods which should be included in all projects
   pod 'FBLazyVector', :path => "#{prefix}/Libraries/FBLazyVector"
   pod 'FBReactNativeSpec', :path => "#{prefix}/React/FBReactNativeSpec"