Steps to reproduce:
1. Create a new project
2. Open Package Manager (Window -> Package Manager)
3. Click the + to open the menu to add packages
4. Select "Add package from disk..."
5. Add the attached extracted Cinemachine package from disk

Expected results: Cinemachine is successfully added to Package Manager, nothing breaks
Actual results: "InvalidCastException: Specified cast is not valid." error is produced, Package Manager UI breaks

Reproducible with: 2019.4.34f1, 2020.3.25f1, 2021.2.7f1, 2022.1.0b1

Notes:
- Not all packages added this way breaks Package Manager, tried adding com.unity.ads and that worked just fine