The namespace is removed in the exported AndroidManifest.xml file when exporting an Android project with a custom manifest

Reproduction steps:
1. Open the attached project "ReproProj"
2. Open Build Settings (File > Build Settings)
3. Switch to Android Platform
4. Make sure “Scenes/SampleScene“ is selected in the Scenes List
5. Select “Export Project”
6. Click “Export”
7. Open “\where-you-placed-your-exported-project\unityLibrary\src\main\AndroidManifest.xml”
8. Search for “enable-feature android:name="com.amazon.device.messaging“

Expected result: “<amazon:enable-feature android:name="com.amazon.device.messaging" android:required="true" />“ exists
Actual result: “<enable-feature android:name="com.amazon.device.messaging" android:required="true" />” is present

Reproducible with: 2023.1.0a16, 6000.0.24f1, 6000.1.0a1
Not reproducible with: 2021.3.45f1, 2022.3.51f1, 2023.1.0a15

Testing environment: Windows 10 Enterprise 21H2
Not reproducible on: No other environment tested

Notes:

• In the “/Assets/Plugins/Android/AndroidManifest.xml“ file the correct tag is present