"Exported activity does not require permission" when attempting to launch from a URI

I am trying to launch an Android app from a URI using this SO question as a reference.

I have a manifest file with the following declared activity:

<activity android:name=".MainActivity">
    <intent-filter>
        <action android:name="android.intent.action.VIEW" />
        <data android:scheme="http" android:host="example.com" />
    </intent-filter>
</activity>

I am attempting to launch MainActivity with the http://example.com link. My issue is that I get the warning

"exported activity does not require permission"

I have looked at other SO questions that report this same warning and all solutions don't seem to work.

How do I write the activity intent-filter correctly to avoid the warning?

Thanks