Exclude an applink subdomain in the entitlements

When dealing with universal links, how can I exclude a specific subdomain? What should I add in my entitlement file if I wanted to exclude help.example.com so that that url is opened in the browser?

My entitlement file looks like:

<?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>com.apple.developer.associated-domains</key>
    <array>
        <string>applinks:www.example.com</string>
        <string>applinks:*.example.com</string>
    </array>
</dict>
</plist>