Merging the 6.28.1 release into master (#6049)

* Update versions for Release 6.28.0

* Release 6.28.0 - GDT cherry pick of #6010 and #6032 (#6035)

* [GDTCORUploadCoordinator startTimer]: don't restart timer if already started (#6032)

* [GDTCORUploadCoordinator startTimer]: don't restart timer if already started

* style

* `GDTCORUploadCoordinator.timer` - nullable

* GDTCORUploadCoordinator test utils thread safety.

* GDTCORFlatFileStorage: keep not expired events when expired batch removed (#6010)

* GDTCORFlatFileStorage: expiration clean up tests

* GDTCORFlatFileStorage: keep not expired events when expired batch removed

* Cleanup

* Cleanup

* Comments

* Comments

* Remove additional delays in tests

* style

* Changelog

* Changelog: remove 7.0.1

* Add #include for config.h to get the value for HAVE_LIBDISPATCH (#6041) (#6042)

Co-authored-by: Denver Coneybeare <dconeybe@google.com>

* M75.1 version bumps (#6043)

* M75.1: Firestore patch release

* Firestore podspec version bump

* Bump Core version

Co-authored-by: Gil <mcg@google.com>
Co-authored-by: Denver Coneybeare <dconeybe@google.com>

Firebase.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name             = 'Firebase'
-  s.version          = '6.28.0'
+  s.version          = '6.28.1'
   s.summary          = 'Firebase'
 
   s.description      = <<-DESC
@@ -36,7 +36,7 @@ Simplify your app development, grow your user base, and monetize more effectivel
   end
 
   s.subspec 'CoreOnly' do |ss|
-    ss.dependency 'FirebaseCore', '6.9.0'
+    ss.dependency 'FirebaseCore', '6.9.1'
     ss.source_files = 'CoreOnly/Sources/Firebase.h'
     ss.preserve_paths = 'CoreOnly/Sources/module.modulemap'
     if ENV['FIREBASE_POD_REPO_FOR_DEV_POD'] then
@@ -91,7 +91,7 @@ Simplify your app development, grow your user base, and monetize more effectivel
 
   s.subspec 'Firestore' do |ss|
     ss.dependency 'Firebase/CoreOnly'
-    ss.dependency 'FirebaseFirestore', '~> 1.16.1'
+    ss.dependency 'FirebaseFirestore', '~> 1.16.2'
   end
 
   s.subspec 'Functions' do |ss|

FirebaseCore.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name             = 'FirebaseCore'
-  s.version          = '6.9.0'
+  s.version          = '6.9.1'
   s.summary          = 'Firebase Core'
 
   s.description      = <<-DESC

FirebaseFirestore.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name             = 'FirebaseFirestore'
-  s.version          = '1.16.1'
+  s.version          = '1.16.2'
   s.summary          = 'Google Cloud Firestore'
 
   s.description      = <<-DESC

Releases/Manifests/6.28.1.json

@@ -0,0 +1,5 @@
+{
+  "Firebase" : "6.28.1",
+  "FirebaseCore" : "6.9.1",
+  "FirebaseFirestore" : "1.16.2"
+}