remove unnecessary waitOnEPStep when current node and the consumer node are in the same stream (#14173)
### Description
Remove the unnecessary WaitOnEPStep if the current operator node and its
consumer are in the same stream while there are notifications filed in
the current node
### Motivation and Context
In the current code, the WaitOnEPStep will always be launched as long as
the notification is filed in the input node, no matter the current node
and the input node are in the same stream or not, which is not
necessary.
This PR is to remove the WaitOnEPStep for this case.
Co-authored-by: Lei Cao <leca@microsoft.com>