P2273R3 Making std::unique_ptr constexpr

- Fix position of 'constexpr' operator<=>(nullptr_t)

Author: jensmaurer

source/support.tex

@@ -593,7 +593,7 @@
 #define @\defnlibxname{cpp_lib_constexpr_dynamic_alloc}@           201907L // also in \libheader{memory}
 #define @\defnlibxname{cpp_lib_constexpr_functional}@              201907L // also in \libheader{functional}
 #define @\defnlibxname{cpp_lib_constexpr_iterator}@                201811L // also in \libheader{iterator}
-#define @\defnlibxname{cpp_lib_constexpr_memory}@                  201811L // also in \libheader{memory}
+#define @\defnlibxname{cpp_lib_constexpr_memory}@                  202202L // also in \libheader{memory}
 #define @\defnlibxname{cpp_lib_constexpr_numeric}@                 201911L // also in \libheader{numeric}
 #define @\defnlibxname{cpp_lib_constexpr_string}@                  201907L // also in \libheader{string}
 #define @\defnlibxname{cpp_lib_constexpr_string_view}@             201811L // also in \libheader{string_view}