message: remove clever use of std::ignore
diff: @@ -153,7 +153,7 @@ namespace vcpkg::Test
  ec.assign(errno, std::system_category());
  }
  #else
  - std::ignore = ec;
  + static_cast<void>(ec);
  vcpkg::Checks::exit_with_message(VCPKG_LINE_INFO, no_filesystem_message);
  #endif
  }
  @@ -175,7 +175,7 @@ namespace vcpkg::Test
  #elif FILESYSTEM_SYMLINK == FILESYSTEM_SYMLINK_UNIX
  ::vcpkg::Test::create_symlink(target, file, ec);
  #else
  - std::ignore = ec;
  + static_cast<void>(ec);
  vcpkg::Checks::exit_with_message(VCPKG_LINE_INFO, no_filesystem_message);
  #endif
  }
  