[cxx-interop] Re-export C++ stdlib in tests that require it

Author: egorzhdan

test/Interop/Cxx/stdlib/Inputs/module.modulemap

@@ -1,26 +1,31 @@
 module StdVector {
   header "std-vector.h"
   requires cplusplus
+  export *
 }
 
 module StdMap {
   header "std-map.h"
   requires cplusplus
+  export *
 }
 
 module StdOptional {
   header "std-optional.h"
   requires cplusplus
+  export *
 }
 
 module StdSet {
   header "std-set.h"
   requires cplusplus
+  export *
 }
 
 module StdPair {
   header "std-pair.h"
   requires cplusplus
+  export *
 }
 
 module MsvcUseVecIt {
@@ -32,9 +37,11 @@ module MsvcUseVecIt {
 module StdUniquePtr {
   header "std-unique-ptr.h"
   requires cplusplus
+  export *
 }
 
 module StdFunction {
   header "std-function.h"
   requires cplusplus
+  export *
 }