Temporarily disable test Reflection/box_descriptors.sil on linux

Author: aschwaighofer

test/Reflection/box_descriptors.sil

@@ -2,6 +2,9 @@
 // RUN: %target-build-swift %s -emit-module -emit-library -module-name capture_descriptors -o %t/capture_descriptors%{target-shared-library-suffix}
 // RUN: %target-swift-reflection-dump -binary-filename %t/capture_descriptors%{target-shared-library-suffix} | %FileCheck %s
 
+// SR-10758
+// UNSUPPORTED: linux
+
 sil_stage canonical
 
 import Builtin