Fix post_install_workaround downgrading development targets (#32633)

Summary:
The `__apply_Xcode_12_5_M1_post_install_workaround` script changes the `IPHONEOS_DEPLOYMENT_TARGET` to `11.0` for all pods. This causes problems if the pods were targetting `12.0` or higher. Many expo modules are targetting `12.0`.

I fixed this issue by checking the existing version and only bumping the target if it is lower than `11.0`.

See also: this discussion post by mikehardy reactwg/react-native-releases#1 (comment)

## Changelog

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[iOS] [Fixed] - __apply_Xcode_12_5_M1_post_install_workaround causing pods targetting iOS 12 and above to fail

Pull Request resolved: #32633

Test Plan:
### Test (failing before this patch, passing after this patch)

1. pick an iOS Pod that has a minimum deployment target of iOS 12 or higher, I chose the Braintree package
2. `npx react-native init myrnapp`
3. Open `ios/Podfile` and add the pod as a dependency: `pod 'Braintree', '~> 5'` (and upgrade the Podfile target to 12 (`platform :ios, '12.0'`))
4. Compile the app.

Before applying this patch: ❌ Build fails because Braintree uses iOS 12 features and was downgraded to target 11.0
After applying this patch: ✅ Build succeeds

Reviewed By: fkgozali

Differential Revision: D32638171

Pulled By: philIip

fbshipit-source-id: 0487647583057f3cfefcf515820855c7d4b16d31

Author: Yonom

scripts/react_native_pods.rb

@@ -548,13 +548,17 @@ def __apply_Xcode_12_5_M1_post_install_workaround(installer)
   # The most reliable known workaround is to bump iOS deployment target to match react-native (iOS 11 now).
   installer.pods_project.targets.each do |target|
     target.build_configurations.each do |config|
-      config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '11.0'
+      # ensure IPHONEOS_DEPLOYMENT_TARGET is at least 11.0
+      should_upgrade = config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'].split('.')[0].to_i < 11
+      if should_upgrade
+        config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '11.0'
       end
+    end
   end
 
   # But... doing so caused another issue in Flipper:
   #   "Time.h:52:17: error: typedef redefinition with different types"
-  # We need to make a patch to RCT-Folly - set `__IPHONE_10_0` to our iOS target + 1.
+  # We need to make a patch to RCT-Folly - remove the `__IPHONE_OS_VERSION_MIN_REQUIRED` check.
   # See https://github.com/facebook/flipper/issues/834 for more details.
-  `sed -i -e  $'s/__IPHONE_10_0/__IPHONE_12_0/' Pods/RCT-Folly/folly/portability/Time.h`
+  `sed -i -e  $'s/ && (__IPHONE_OS_VERSION_MIN_REQUIRED < __IPHONE_10_0)//' Pods/RCT-Folly/folly/portability/Time.h`
 end