[PodTargetInstaller] Fix the CONFIGURATION_BUILD_DIR var for resource bundles

It was recursively defined before, which led to the target build product being scoped one level to deep.

lib/cocoapods/installer/target_installer/pod_target_installer.rb

@@ -177,7 +177,7 @@ module Pod
               c.build_settings['PRODUCT_NAME'] = bundle_name
               relative_info_plist_path = info_plist_path.relative_path_from(sandbox.root)
               c.build_settings['INFOPLIST_FILE'] = relative_info_plist_path.to_s
-              c.build_settings['CONFIGURATION_BUILD_DIR'] = target.configuration_build_dir
+              c.build_settings['CONFIGURATION_BUILD_DIR'] = target.configuration_build_dir('$(BUILD_DIR)/$(CONFIGURATION)$(EFFECTIVE_PLATFORM_NAME)')
 
               # Set the correct device family for this bundle, based on the platform
               device_family_by_platform = {

spec/unit/installer/target_installer/pod_target_installer_spec.rb

@@ -190,7 +190,7 @@ module Pod
 
           it 'sets the correct build dir' do
             @bundle_target.build_configurations.each do |bc|
-              bc.build_settings['CONFIGURATION_BUILD_DIR'].should == '$CONFIGURATION_BUILD_DIR/BananaLib-Pods-SampleProject'
+              bc.build_settings['CONFIGURATION_BUILD_DIR'].should == '$(BUILD_DIR)/$(CONFIGURATION)$(EFFECTIVE_PLATFORM_NAME)/BananaLib-Pods-SampleProject'
             end
           end