FDL Sample App: Fixing imports and Pod file (#5952)

* Fixing imports and Pod file

FirebaseDynamicLinks/Tests/Sample/FDLBuilderTestAppObjC/AppDelegate.m

@@ -17,8 +17,8 @@
 #import "AppDelegate.h"
 #import "ViewController.h"
 
+#import <FirebaseCore/FirebaseCore.h>
 #import <FirebaseDynamicLinks/FIRDynamicLinks.h>
-#import "FirebaseCore/Sources/Private/FirebaseCoreInternal.h"
 
 @implementation AppDelegate
 

FirebaseDynamicLinks/Tests/Sample/Podfile

@@ -9,5 +9,6 @@ target 'FDLBuilderTestAppObjC' do
   pod 'FirebaseInstallations', :path => '../../../'
   pod 'FirebaseInstanceID', :path => '../../../'
   pod 'FirebaseDynamicLinks', :path => '../../../'
+  pod 'GoogleUtilities', :path => '../../../'
 
 end