How to reproduce:
1. Open the attached project "URP-Blend Styles.zip"
2. Open the "SampleScene" Scene
3. Select the "MultiplyLight" GameObject in the Hierarchy window
4. Change the Blend Style in the Inspector window to "Additive"
Expected result: Shadows are rendered from both Light sources, despite both 2D Lights having different Blend Styles
Actual result: Only one source of Light casts a shadow
Reproducible with: 12.0.0 (2021.2.0b1, 2021.2.0b15, 2022.1.0a1), 12.1.6 (2021.2.19f1), 13.1.7 (2022.1.0b15), 14.0.2 (2022.2.0a9)
Not reproducible with: 7.7.1 (2019.4.37f1), 10.8.1 (2020.3.33f1), 12.0.0 (2021.2.0a21)