How to reproduce:
1. Open the “ReproLightsProject“
2. Open the “LightPixelRepro“ scene
3. Observe the Game view

Expected result: No pixelation artifact
Actual result: A visible pixelation artifact

Reproducible with: 2021.3.44f1, 2022.3.49f1, 6000.0.22f1

Reproducible on: macOS 14.6.1 (Intel)
Not reproducible on: Windows 10 Pro (22H2)

Notes:
- The 33 lights in the scene start to create the pixel artifact, but they are better visible with around 40, the light limit in HDRP is 63, so the light amount that reproduces the issue is a lot less than the limit
- The pixel artifact position depends on the Scene/Game view cameras position, if you move it around the pixel artifacts change positions
- Reproducible in the Player macOS
- More information in the comments