onnxruntime

Make 'env' argument to Session const (#13362)

### Description
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The Env argument does not need to be mutable to call the underlying C
API. Update the Ort::Session ctor to have a const Env.

All other changes are from clang-format running. 

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