AppConnect Error with AppIntentVocabulary and INMessageSendItent

I was trying to submit my app yesterday (Xcode 10 B6), but I keep getting the below error. Is this an Xcode bug or is there something wrong with my vocabulary file?

App Store Connect Operation Error

ERROR ITMS-90624: "Invalid Intent Vocabulary. The AppIntentVocabulary.plist file in the Payload/SignificantOther.app folder can't contain the intent name "INMessageSendIntent"."

INTENT INFO.PLIST

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">

<plist version="1.0">

<dict>

<key>IntentPhrases</key>

<array>

<dict>

<key>IntentName</key>

<string>INMessageSendIntent</string>

<key>IntentExamples</key>

<array>

<string>Send a new message with Significant Other</string>

<string>Send my Significant Other a new message</string>

<string>Tell my Significant Other</string>

</array>

</dict>

</array>

</dict>

</plist>

AppIntentVocabulary.plist

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">

<plist version="1.0">

<dict>

<key>IntentPhrases</key>

<array>

<dict>

<key>IntentName</key>

<string>INMessageSendIntent</string>

<key>IntentExamples</key>

<array>

<string>Send a new message with Significant Other</string>

<string>Send my Significant Other a new message</string>

<string>Tell my Significant Other</string>

</array>

</dict>

</array>

</dict>

</plist>