Apply suggestions from code review

Author: ncooke3

Firestore/Example/GoogleBenchmark.podspec

@@ -35,7 +35,7 @@ Google's C++ benchmark framework.
 
   s.ios.deployment_target = '15.0'
   s.osx.deployment_target = '10.15'
-  s.ios.deployment_target = '15.0'
+  s.tvos.deployment_target = '15.0'
 
   s.requires_arc = false
 

Firestore/Example/GoogleTest.podspec

@@ -35,7 +35,7 @@ Google's C++ test framework.
 
   s.ios.deployment_target = '15.0'
   s.osx.deployment_target = '10.15'
-  s.ios.deployment_target = '15.0'
+  s.tvos.deployment_target = '15.0'
 
   s.requires_arc = false
 

Firestore/Example/LibFuzzer.podspec

@@ -30,7 +30,7 @@ Pod::Spec.new do |s|
 
   s.ios.deployment_target = '15.0'
   s.osx.deployment_target = '10.15'
-  s.ios.deployment_target = '15.0'
+  s.tvos.deployment_target = '15.0'
 
   s.source              = {
     :git => 'https://github.com/llvm/llvm-project.git'

Firestore/Example/ProtobufCpp.podspec

@@ -31,7 +31,7 @@ Pod::Spec.new do |s|
 
   s.ios.deployment_target = '15.0'
   s.osx.deployment_target = '10.15'
-  s.ios.deployment_target = '15.0'
+  s.tvos.deployment_target = '15.0'
 
   s.source_files = 'src/**/*.{h,cc,inc}',
                    # utf8_range is needed too, to avoid build errors.

GoogleAppMeasurement.podspec

@@ -23,7 +23,7 @@ Pod::Spec.new do |s|
 
     s.ios.deployment_target = '15.0'
     s.osx.deployment_target  = '10.15'
-    s.ios.deployment_target = '15.0'
+    s.tvos.deployment_target = '15.0'
 
     s.libraries  = 'c++', 'sqlite3', 'z'
     s.frameworks = 'StoreKit'