How to reproduce:
1. Open project "ParticleBug.zip"
2. Enter "SampleScene" Scene (Assets>Scenes>SampleScene)
3. In the Hierarchy window select "Particle System"
4. Look at the Scene or Game window and observe the speed of the particles
5. In the Inspector window scroll down to the "Texture Sheet Animation" tab and expand it
6. Change Animation to "Whole Sheet"
7. Look at the Scene or Game window and observe the speed of the particles

Expected result: Speed of animation should be the same in both animations
Actual result: With animation "Single Row" the speed is slower

Reproducible with: 2019.4.31f1, 2020.3.20f1, 2021.1.25f1, 2021.2.0b16, 2022.1.0a12

Notes:
- If the Animation is "Single Row" you need to multiply the FPS by the number of rows (20x8=160) to see the animations play at the correct speed