How to reproduce:
1. Open the attached "CharacterBug.zip" project
2. Open the "SampleScene" Scene
3. Select the "Capsule" GameObject in the Hierarchy window
4. Enter Play Mode
5. Press and hold the A key to move the "Capsule" GameObject to the platforms
6. Observe how the Character Controller behaves when it hits the last platform in the Game view

Expected result: Character Controller with Step Offset value of 0.8 stays in the air (1.08 on the Y-axis) when hits the last platform, which is of height 2
Actual result: Character Controller with Step Offset value of 0.8 is snapped downwards to ~0.295 on the Y-axis when hits the last platform, which is of height 2

Reproducible with: 2018.4.26f1, 2019.4.7f1, 2020.1.1f1, 2020.2.0a20

Notes:
- If the Step Offset value is increased to 0.9, the Character Controller gets snapped downwards to ~0.18 on the Y-axis
- If the Step Offset value is set to 0.6, the Character Controller stays in the air, so it snaps downwards only when the Character Controller's Step Offset value is very close to the height needed to step on the GameObject