Custom terrain lighting is inverted compared to Unity Terrain when rotating directional light on X axis

How to reproduce:
1. Open the “IN-110952_HDRP_Terrain“ project
2. Open the “TestScene”
3. In the Inspector expand the “Continent Lighting” GameObject and select “Sun”
4. In the Inspector set the “Sun” Transform Rotation X,Y,Z values to 0
5. Rotate the “Sun” on the X axis until the value is around 25
6. Observe the terrain on the left

Expected result: The terrain appears bright
Actual result: The terrain appears dark

Reproducible with: 2023.3.0b6, 6000.0.56f1, 6000.2.2f1, 6000.3.0a6
Could not test with: 2023.3.0b5 (Compilation errors)

Reproducible on: macOS 15.6 (M1 Max), Windows 11 (by user)
Not reproducible on: no other environments tested

Note: The custom terrain on the left is expected to appear similar to the Unity Terrain on the right