Restructure MacOS framework package to fix malformed Framework errors (#21536)
### Description
Refactor framework directory structure for MacOS packages
### Motivation and Context
<!-- - Why is this change required? What problem does it solve?
- If it fixes an open issue, please link to the issue here. -->
Apple started enforcing specific [framework
structure](https://developer.apple.com/library/archive/documentation/MacOSX/Conceptual/BPFrameworks/Concepts/FrameworkAnatomy.html)
for MacOS packages. We need to change how we package for MacOS to follow
the guidelines
Fixes following issue: [Malformed
Framework](https://github.com/microsoft/onnxruntime-swift-package-manager/issues/19
)