Shared variable's OnValueChanged callback is not raised when the value is changed

Steps to reproduce:

1. Install `com.unity.behavior` 1.0.10
2. Create a Blackboard asset and add a Blackboard Variable of type integer (named "Shared Integer")
3. Make the blackboard variable both Exposed and Shared
4.  Create a Behavior Graph asset and linked the blackboard asset
5.  Add and linked to On Start a Run In Parallel node with two branches
   1. Branch 1: Wait (Second) -> SetVariableValue (set "Shared Integer" to 1)
   2. Branch 2: WaitForVariableChange (custom node, see Notes below) -> LogVariableValue ("Shared Integer")
6. Attach the graph to a gameObject
7. Enter playmode

Actual results: 

• No log because WaitForVariableChange keeps waiting

Expected results: 

• Log the value of the "Shared Integer" variable

Reproducible with versions: 
1.0.8

Not reproducible with versions: 
1.0.7 or below

Can’t test with versions: 

Tested on (OS): 
WinEditor/WinPlayer

Notes:

• WaitForVariableChange is from this thread: https://discussions.unity.com/t/proper-way-to-run-a-branch-by-variable-change/1681803/4