Update podspecs to properly separate privacy manifest files

Summary:
As pointed out in the GitHub issues, if `resources` is used in the podspec instead of explicitly named `resource_bundles`, the associated files will be placed in the root bundle of the app. In this case, this means the `PrivacyInfo.xcprivacy` files for each framework of IGListKit would end up overwriting each other, and ultimately overwriting the manifest of the app itself.

This diff configures the podspecs correctly to ensure there are no file conflicts.

Reviewed By: benhgreen

Differential Revision: D55056568

fbshipit-source-id: 85951afbc93c847a40caca64d7b930df74ff705d

IGListDiffKit.podspec

@@ -23,7 +23,7 @@ Pod::Spec.new do |s|
   s.source_files = 'Source/IGListDiffKit/**/*.{h,m,mm}'
   s.private_header_files = 'Source/IGListDiffKit/Internal/*.h'
 
-  s.resources = ['Source/PrivacyInfo.xcprivacy']
+  s.resource_bundles = { "#{s.name}_Privacy" => ['Source/PrivacyInfo.xcprivacy'] }
   s.requires_arc = true
 
   s.ios.deployment_target = '11.0'

IGListKit.podspec

@@ -35,7 +35,7 @@ Pod::Spec.new do |s|
 
   s.osx.source_files = 'Source/IGListKit/IGListKit.h'
 
-  s.resources = ['Source/PrivacyInfo.xcprivacy']
+  s.resource_bundles = { "#{s.name}_Privacy" => ['Source/PrivacyInfo.xcprivacy'] }
   s.requires_arc = true
 
   s.ios.deployment_target = '11.0'

IGListSwiftKit.podspec

@@ -28,7 +28,7 @@ Pod::Spec.new do |s|
     ]
   end
 
-  s.resources = ['Source/PrivacyInfo.xcprivacy']
+  s.resource_bundles = { "#{s.name}_Privacy" => ['Source/PrivacyInfo.xcprivacy'] }
   s.requires_arc = true
 
   s.swift_versions = ['4.0', '5.0', '5.1']