Merge release 6.20.0 (#5118)

Author: ryanwilson

Firebase.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name             = 'Firebase'
-  s.version          = '6.19.0'
+  s.version          = '6.20.0'
   s.summary          = 'Firebase for iOS (plus community support for macOS and tvOS)'
 
   s.description      = <<-DESC
@@ -91,7 +91,7 @@ Simplify your iOS development, grow your user base, and monetize more effectivel
 
   s.subspec 'Firestore' do |ss|
     ss.dependency 'Firebase/CoreOnly'
-    ss.dependency 'FirebaseFirestore', '~> 1.11.1'
+    ss.dependency 'FirebaseFirestore', '~> 1.11.2'
   end
 
   s.subspec 'Functions' do |ss|