[Make.config] Bump for Xcode 9.4 beta 2 (#4017)

Make.config

@@ -56,8 +56,8 @@ IOS_PACKAGE_VERSION_BUILD=$(IOS_COMMIT_DISTANCE)
 IOS_PACKAGE_UPDATE_ID=$(shell printf "2%02d%02d%02d%03d" $(IOS_PACKAGE_VERSION_MAJOR) $(IOS_PACKAGE_VERSION_MINOR) $(IOS_PACKAGE_VERSION_REV) $(IOS_PACKAGE_VERSION_BUILD))
 
 XCODE_VERSION=9.4
-XCODE_URL=http://xamarin-storage/bot-provisioning/xcodes/Xcode_9.4_beta.xip
-XCODE_DEVELOPER_ROOT=/Applications/Xcode94-beta1.app/Contents/Developer
+XCODE_URL=http://xamarin-storage/bot-provisioning/xcodes/Xcode_9.4_beta2.xip
+XCODE_DEVELOPER_ROOT=/Applications/Xcode94-beta2.app/Contents/Developer
 
 # Minimum Mono version
 MIN_MONO_VERSION=5.8.0.0