Baked reflection probes are not updated when baking using the "Generate Lighting" button to until you bake twice (without changing anything in the scene that would invalidate the bake). This seems to only occur consistently after the first bake has been performed.

Repro steps:
1. Open the SampleScene scene in the reproduction project
2. Bake lighting using the "Generate Lighting" button
3. Observe the reflection probe preview or the reflective sphere in the scene
4. Move the cube in the scene enough that the difference should be visible in the reflection
5. Bake the scene again using the "Generate Lighting" button
6. Observe that the reflection probe preview and reflective sphere have not changed appearance
7. Bake the scene again using the "Generate Lighting" button
8. Observe that the reflection probe preview and reflective sphere have changed appearance now

Expected behavior: Baking the scene once updates reflection probe previews, baked cubemaps and the look of reflective surfaces
Actual behavior: Two bakes with the exact same settings must be performed for the appearance to update.

Reproduces on: 2021.2.0a15, 2019.3.0f3
Doesn't reproduce on: 2018.4.20f1, 2018.4.34f1

Notes:
- The error does not occur when using the "Bake" button on the reflection probe inspector or the "Bake Reflection Probes" dropdown option under the "Generate Lighting" button.
- Clearing the GI Cache lets the next bake generate correct results. Subsequent bakes will still be incorrect.