[libcxx] [test] Remove a LIBCXX-WINDOWS-FIXME, don't test an unsupported strftime() pattern

[mstorsjo]

Summary

Testing the unsupported pattern can trigger the invalid parameter handler,
which depending on CRT configuration can abort the process.

Split this out from D112211, as this XFAIL actually can be fixed pretty
easily.

[mstorsjo]

Rebase and rerun CI

[mstorsjo]

Ping

libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put2.pass.cpp

 //===----------------------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
-// XFAIL: LIBCXX-WINDOWS-FIXME
-
 // <locale>
 
 // class time_put<charT, OutputIterator>
 
 // iter_type put(iter_type s, ios_base& str, char_type fill, const tm* t,
 //               char format, char modifier = 0) const;
 
 #include <locale>
std::ios ios(0);
         std::string ex(str, iter.base());
 //        assert(ex == "EDT");  depends on time zone
     }
     {
         iter = f.put(output_iterator<char*>(str), ios, '*', &t, 'z');
         std::string ex(str, iter.base());
 //        assert(ex == "-0400");  depends on time zone
     }
+#ifndef _WIN32
+    // The Windows strftime() doesn't support the "%+" format. Depending on CRT
+    // configuration of the invalid parameter handler, this can abort the process.
     {
         iter = f.put(output_iterator<char*>(str), ios, '*', &t, '+');
         std::string ex(str, iter.base());
 //        assert(ex == "Sat May  2 13:03:06 EDT 2009");  depends on time zone
     }
+#endif
     {
         iter = f.put(output_iterator<char*>(str), ios, '*', &t, '%');
         std::string ex(str, iter.base());
         assert(ex == "%");
     }
 
   return 0;
 }