How to reproduce:
1. Open user's attached project "BugScenario"
2. Enter Game mode
3. Press "space" key once

Expected result: the door will turn 120 degrees and enter trigger, starting to call OnTriggerStay continuously
Actual result: the door enters trigger as expected but continuously calls OnTriggerEnter and OnTriggerExit instead of OnTirggerStay

Reproduced with: 5.6.5p3, 2017.1.3p3, 2017.2.2p3, 2017.3.2f1, 2017.4.1f1, 2018.1.0b13, 2018.2.0a7

Note: the problem seems to be created inside "door.cs" line 82 where every frame RigidBody rotation is set to (previous rotation * rotation delta). Also after setting RigidBody to Continuous or Continuous Dynamic Collision Detection, it seems to trigger all three Trigger events (OnTriggerEnter, OnTriggerExit, OnTriggerStay).