Updating existing AnimationClip import setting results in a new InternalID and lost references to the clip

How to reproduce:
1. Open the attached project ("case-1157349-AssetImporter.zip")
2. Open Window -> Animation Events Test
3. Set the clip to "Take 001"
4. Press the "AddEvent" button

Expected results: AnimationClip's Internal ID remains the same and the reference to it remains
Actual results: AnimationClip's Internal ID changes and all references to it are lost

Reproducible with: 2019.4.0f1, 2019.4.38f1, 2020.3.9f1, 2021.2.0a1, 2021.2.0a14,
Not reproducible with: 2020.3.10f1, 2020.3.33f1, 2021.2.0a15, 2021.2.19f1, 2021.3.1f1, 2022.1.0f1, 2022.2.0a11