Bugfix: set CMAKE_OSX_DEPLOYMENT_TARGET for iOS, watchOS, tvOS - #6566

closes: #6542
Changelog: Bugfix: set CMAKE_OSX_DEPLOYMENT_TARGET for iOS, watchOS and tvOS.
Docs: omit

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^{Note: By default this PR will skip the slower tests and will use a limited set of python versions. Check here how to increase the testing level by writing some tags in the current PR body text.}