onnxruntime

Python API to check whether collective ops are available or not (#17730)

Python API to check whether collective ops are available or not

### Description
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Adding an API to check whether collective ops are available or not.
Since there is no independent MPI enabled build, this flag can be used
on Python front for branching. Specifically, to conditionally enable
tests.

### Motivation and Context
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- If it fixes an open issue, please link to the issue here. -->

Flag to be used in Python to check whether onnxruntime supports
collective ops or not. Handy for conditionally enabling/disabling tests
and for other branching decisions.