WP level instance runtime settings affect streaming generation

If a level instance uses different runtime settings then it can override the main WP's runtime settings with UWorldPartitionRuntimeSpatialHash::ApplyCVars

Runtime settings:

• GRuntimeSpatialHashUseAlignedGridLevels
• GRuntimeSpatialHashSnapNonAlignedGridLevelsToLowerLevels
• GRuntimeSpatialHashPlaceSmallActorsUsingLocation
• GRuntimeSpatialHashPlacePartitionActorsUsingLocation

1. Create a WP level and place some actors around.
2. Create a WP level instance with some actors in it.
3. Enter PIE.
4. Look at the streaming generation log.
5. Open (not edit) level instance from step 2.
6. In world partition setup of world settings:
   1. enable streaming
   2. enable "Use Aligned Grid Levels"
   3. disable streaming
   4. save
7. Open original WP level from step 1.
8. Enter PIE and exit pie a few times.
9. Look at the streaming generation logs which can vary between PIE sessions.