[test] Fix stdlib/Reflection_objc.swift with newer deployment target

This test stops working with deployment targets that no longer link
@rpath/libswiftCoreGraphics.dylib when running on OSes that still
require the CoreGraphics overlay. Explicitly link it to workaround.

Author: benlangmuir

test/stdlib/Reflection_objc.swift

@@ -1,7 +1,9 @@
 // RUN: %empty-directory(%t)
 //
 // RUN: %target-clang %S/Inputs/Mirror/Mirror.mm -c -o %t/Mirror.mm.o -g
-// RUN: %target-build-swift -parse-stdlib %s -module-name Reflection -I %S/Inputs/Mirror/ -Xlinker %t/Mirror.mm.o -o %t/a.out
+// Note: explicitly link the CoreGraphics overlay because does not get autolinked
+// and it is needed for conformances on macOS < 15.
+// RUN: %target-build-swift -parse-stdlib %s -module-name Reflection -I %S/Inputs/Mirror/ -Xlinker %t/Mirror.mm.o -o %t/a.out -lswiftCoreGraphics
 // RUN: %target-codesign %t/a.out
 // RUN: %{python} %S/../Inputs/timeout.py 360 %target-run %t/a.out %S/Inputs/shuffle.jpg | %FileCheck %s
 // FIXME: timeout wrapper is necessary because the ASan test runs for hours