Reproduction steps:
1. Open the attached project;
2. Enter Play mode and go to the cube;

Actual result: the character collides with the cube, although CharacterController.detectCollisions is set to false (actualResult_detectCollisions.gif).
Expected result: according to the documentation (https://docs.unity3d.com/ScriptReference/CharacterController-detectCollisions.html), if CharacterController.detectCollisions is set to false, the character should ignore any collisions with other objects. The character should walk through the cube (expectedResult_detectCollisions.gif).

Reproduced with: 5.3.6p4, 5.4.3f1, 5.5.0f1, 5.5.0f3, 5.6.0b6