Reproduction steps:
1. Open the attached project “UWPProject”
2. Ensure Mobile Notification v2.3.0 is installed
3. Build the project for Universal Windows Platform
4. Observe the build process

Expected result: The build is completed successfully
Actual result: Build failed with the error “mobilenotifications.androidlib is a directory, which is not supported”

Reproducible with: 2.3.0(2021.3.33f1, 2022.3.15f1, 2023.2.4f1, 2023.3.0a18)
Not reproducible with: 2.2.0, 2.2.1, 2.2.2 (2021.3.33f1, 2022.3.15f1, 2023.2.4f1, 2023.3.0a18)

Testing environment: Windows 10 Pro 22H2

Full error:
Building C:\Projects\FreshProject\Unity2022\Deploy\UWP\Unity2022\Plugins\mobilenotifications.androidlib failed with output:
The source path Library\PackageCache\com.unity.mobile.notifications@2.3.0\Runtime\Android\Plugins\mobilenotifications.androidlib is a directory, which is not supported.
UnityEditor.BuildPipeline:BuildPlayer (UnityEditor.BuildPlayerOptions)
BuildScript:BuildForPlatform (UnityEditor.BuildTarget,string[],string,string) (at Assets/Scripts/Editor/BuildScript.cs:42)
BuildScript:Build () (at Assets/Scripts/Editor/BuildScript.cs:18)

Notes: Building works fine for other platforms, Android, Standalone (macOS and Windows)