Disable this test for now...

The underlying behavior of __SwiftValue bridging now has
a couple of different possible behaviors depending on how
libswiftCore was built and even (in some cases) the specific binary that's
running.

This makes it very hard to craft an accurate test of this functionality.
Disable it (for now) until we can figure out a better way to
conditionalize the expected behavior here.

Author: tbkka

test/stdlib/SwiftValueNSObject.swift

@@ -21,6 +21,7 @@
 // REQUIRES: executable_test
 
 // REQUIRES: objc_interop
+// REQUIRES: rdar127008956
 
 // UNSUPPORTED: use_os_stdlib
 // UNSUPPORTED: back_deployment_runtime