[iOS] Update podspec to use install_modules_dependencies (#2635)

This change updates the RNGestureHandler.podspec to consume the
`install_modules_dependencies` function provided by React Native to
configure the pods dependencies.
Thanks to using this function, whenever we update the function in React
Native, the library will automatically benefit from it.
This will make the library more future proof and more resilient to
changes in React Native

This allow RNGestureHandler to work also with frameworks, as before the
change, it failed to build when `use_frameworks!` was set in RN 0.72.x

## Test plan

Tested locally:

Before changes
1. Created a new app with `npx react-native init RNFrameworks --version
latest --skip-install`
1. `cd RNFrameworks`
1. `yarn add react-native-gesture-handler`
1. `yarn install`
1. `cd ios`
1. `NO_FLIPPER=1 USE_FRAMEWORKS=static RCT_NEW_ARCH_ENABLED=1 bundle
exec pod install`
1. `open RNFrameworks`
1. build and run and observe it failing because it can't find files in
react/utils and react/debug

After Changes
1. Reinstall pods `NO_FLIPPER=1 USE_FRAMEWORKS=static
RCT_NEW_ARCH_ENABLED=1 bundle exec pod install`
1. `open RNFrameworks`
1. build and run and observe it succeeding

RNGestureHandler.podspec

@@ -1,29 +1,18 @@
 require "json"
 
-fabric_enabled = ENV['RCT_NEW_ARCH_ENABLED'] == '1'
+new_arch_enabled = ENV['RCT_NEW_ARCH_ENABLED'] == '1'
+apple_platform = new_arch_enabled ? '11.0' : '9.0'
 
-Pod::Spec.new do |s|
-  # NPM package specification
-  package = JSON.parse(File.read(File.join(File.dirname(__FILE__), "package.json")))
-
-  s.name         = "RNGestureHandler"
-  s.version      = package["version"]
-  s.summary      = package["description"]
-  s.homepage     = "https://github.com/software-mansion/react-native-gesture-handler"
-  s.license      = "MIT"
-  s.author       = { package["author"]["name"] => package["author"]["email"] }
-  s.source       = { :git => "https://github.com/software-mansion/react-native-gesture-handler", :tag => "#{s.version}" }
-  s.source_files = "ios/**/*.{h,m,mm}"
-  s.requires_arc = true
-
-  if fabric_enabled
+# Utility function to install dependencies if React Native's
+# install_modules_dependencies is not defined
+def install_dependencies(s, new_arch_enabled)
+  if new_arch_enabled
     folly_compiler_flags = '-DFOLLY_NO_CONFIG -DFOLLY_MOBILE=1 -DFOLLY_USE_LIBCPP=1 -Wno-comma -Wno-shorten-64-to-32'
 
     s.pod_target_xcconfig = {
       'HEADER_SEARCH_PATHS' => '"$(PODS_ROOT)/boost" "$(PODS_ROOT)/boost-for-react-native" "$(PODS_ROOT)/RCT-Folly"',
       'CLANG_CXX_LANGUAGE_STANDARD' => 'c++17',
     }
-    s.platforms       = { ios: '11.0', tvos: '11.0' }
     s.compiler_flags  = folly_compiler_flags + ' -DRCT_NEW_ARCH_ENABLED'
 
     s.dependency "React"
@@ -34,8 +23,28 @@ Pod::Spec.new do |s|
     s.dependency "RCTTypeSafety"
     s.dependency "ReactCommon/turbomodule/core"
   else
-    s.platforms = { :ios => "9.0", :tvos => "9.0" }
-
     s.dependency "React-Core"
   end
 end
+
+Pod::Spec.new do |s|
+  # NPM package specification
+  package = JSON.parse(File.read(File.join(File.dirname(__FILE__), "package.json")))
+
+  s.name         = "RNGestureHandler"
+  s.version      = package["version"]
+  s.summary      = package["description"]
+  s.homepage     = "https://github.com/software-mansion/react-native-gesture-handler"
+  s.license      = "MIT"
+  s.author       = { package["author"]["name"] => package["author"]["email"] }
+  s.source       = { :git => "https://github.com/software-mansion/react-native-gesture-handler", :tag => "#{s.version}" }
+  s.source_files = "ios/**/*.{h,m,mm}"
+  s.requires_arc = true
+  s.platforms       = { ios: apple_platform, tvos: apple_platform }
+
+  if defined?(install_modules_dependencies()) != nil
+    install_modules_dependencies(s);
+  else
+    install_dependencies(s, new_arch_enabled)
+  end
+end