Fix warnings in array and assoc containers

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@242629 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/containers/sequences/array/begin.pass.cpp

@@ -14,6 +14,8 @@
 #include <array>
 #include <cassert>
 
+#include "suppress_array_warnings.h"
+
 int main()
 {
     {
@@ -27,6 +29,4 @@ int main()
         *i = 5.5;
         assert(c[0] == 5.5);
     }
-    {
-    }
 }