[Heartbeat Logging] Update FirebaseCore dependents for heartbeat logging changes (#9436)

* Set swift_version to 5.3 for core dependents

* Fix Firestore Cmake build

* s/Cmake/CMake

FirebaseInAppMessaging.podspec

@@ -20,6 +20,8 @@ See more product details at https://firebase.google.com/products/in-app-messagin
   s.ios.deployment_target = '10.0'
   s.tvos.deployment_target = '10.0'
 
+  s.swift_version = '5.3'
+
   s.cocoapods_version = '>= 1.4.0'
   s.prefix_header_file = false