[v11] Update minimum platform dependencies (#60)

AppCheckCore.podspec

@@ -17,10 +17,10 @@ Pod::Spec.new do |s|
   }
   s.social_media_url = 'https://twitter.com/Firebase'
 
-  ios_deployment_target = '11.0'
-  osx_deployment_target = '10.13'
-  tvos_deployment_target = '12.0'
-  watchos_deployment_target = '6.0'
+  ios_deployment_target = '12.0'
+  osx_deployment_target = '10.15'
+  tvos_deployment_target = '13.0'
+  watchos_deployment_target = '7.0'
 
   s.swift_version = '5.5'
 
@@ -43,7 +43,7 @@ Pod::Spec.new do |s|
   s.osx.weak_framework = 'DeviceCheck'
   s.tvos.weak_framework = 'DeviceCheck'
 
-  s.dependency 'PromisesObjC', '~> 2.3'
+  s.dependency 'PromisesObjC', '~> 2.4'
   s.dependency 'GoogleUtilities/Environment', '~> 8.0'
   s.dependency 'GoogleUtilities/UserDefaults', '~> 8.0'