Auto merge of #118644 - madsmtm:macos-weak-linking-test, r=compiler-errors

Add test for Apple's `-weak_framework` linker argument

The [`-weak_framework`](https://developer.apple.com/library/archive/documentation/MacOSX/Conceptual/BPFrameworks/Concepts/WeakLinking.html) linker argument can sometimes be useful to reduce startup times, and to link newer frameworks while still having older deployment targets.

So I made a test to ensure that it continues to work.

Discussed in rust-lang/rust#99427.

Author: bors