Updated the platform detect for darwin to use sw_ver for release

[aaronlippold]

Description

Updated the detect for osx to use sw_vers to get the actual os release vs the kernel version

• I have read the CONTRIBUTING document.

[chef-expeditor]

Hello aaronlippold! Thanks for the pull request!

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Thank you for contributing!

[em-c-rod]

LGTM 👍