How to reproduce:
1. Open attached project "BatchTestProject.zip" with -force-gles32 argument command
2. Open scene "BatchTest"
3. Open and enable Window -> Analysis -> Frame Debugger
4. In Project window, select and observe two materials "New Material 1" and "New Material" (all the values are the same)
5. Observe Frame Debugger -> Render Main Shadowmap -> ShadowLoopNewBatcher.Draw -> SRP Batch (only single SRP Batch is present)
6. In Project window, select "New Material"
7. Change any value
8. Observe Frame Debugger -> Render Main Shadowmap -> ShadowLoopNewBatcher.Draw -> SRP Batch

Expected result: only one SRP Batch is present
Actual result: two SRP Batches are present

Reproducible with: 2019.4.3f1 (URP 7.3.1), 2020.1.0b16 (8.1.0), 2020.2.0a10 (9.0.0-preview.35)
Could not test with: 2018.4.25f1 (4.10.0-preview), 2020.2.0a11, 2020.2.0a17 (the Editor crashes upon load up due to other bug)

Multiple 'Render Main Shadowmap' -> '... Draw' -> 'SRP Batch'es are present when multiple materials with different properties are present