Re-work OrtApi struct to satisfy C++20 compilers (#15183)
### Description
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Remove `deletion` of copy functions from `OrtApi` as its initialization
no longer compiles in C++20.
Introduce a non-copyable member to implicitly delete copy ctor.
### Motivation and Context
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- If it fixes an open issue, please link to the issue here. -->
Inspired by https://github.com/microsoft/onnxruntime/pull/14901
Solution credits: @RyanUnderhill
Cc: @georgthegreat
