temporarily disable Interop/Cxx/stdlib/libstdcxx-module-interface.swift

rdar://91518316

Author: eeckstein

test/Interop/Cxx/stdlib/libstdcxx-module-interface.swift

@@ -3,6 +3,8 @@
 // This test is specific to libstdc++ and only runs on platforms where libstdc++ is used.
 // REQUIRES: OS=linux-gnu
 
+// REQUIRES: rdar91518316
+
 // CHECK-STD: enum std {
 // CHECK-STD:   enum __cxx11 {
 // CHECK-STD:     struct __CxxTemplateInstNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE {