Build media and live-kit in test-mode on non-MacOS (#6859)

Build media and live-kit in test-mode on non-MacOS (Related to
https://github.com/zed-industries/zed/issues/5391
https://github.com/zed-industries/zed/issues/5395
https://github.com/zed-industries/zed/issues/5394)

This makes it possible to build the media and live-kit crates on
non-MacOS

Release Notes:

- N/A

crates/media/src/bindings.rs

@@ -3,6 +3,8 @@
 #![allow(non_snake_case)]
 #![allow(unused)]
 
+#[cfg(target_os = "macos")]
 use objc::*;
 
+#[cfg(target_os = "macos")]
 include!(concat!(env!("OUT_DIR"), "/bindings.rs"));