upgrade GMA dependency min version required

Author: elneruda

TeadsAdMobAdapter.podspec

@@ -20,7 +20,7 @@ Pod::Spec.new do |s|
     s.source_files              = ['MediationAdapters/TeadsAdMobAdapter/**/*{.swift}', 'MediationAdapters/Common/*{.swift}']
     s.exclude_files             = ['MediationAdapters/TeadsAdMobAdapter/Exports.swift']
     s.dependency                'TeadsSDK', s.version.to_s
-    s.dependency                'Google-Mobile-Ads-SDK', '>= 8.0'
+    s.dependency                'Google-Mobile-Ads-SDK', '>= 9.0.0'
 
     s.pod_target_xcconfig       = { 'EXCLUDED_ARCHS[sdk=iphonesimulator*]' => 'i386' }
     s.user_target_xcconfig      = { 'EXCLUDED_ARCHS[sdk=iphonesimulator*]' => 'i386' }