Remove mentions of implementation in Libc++ 21, should go to Libc++ 22, also remove check_assertion.h header in test due to it breaking

Author: smallp-o-p

libcxx/docs/ReleaseNotes/21.rst

@@ -53,7 +53,6 @@ Implemented Papers
 - P2711R1: Making multi-param constructors of ``views`` ``explicit`` (`Github <https://github.com/llvm/llvm-project/issues/105252>`__)
 - P2770R0: Stashing stashing ``iterators`` for proper flattening (`Github <https://github.com/llvm/llvm-project/issues/105250>`__)
 - P2655R3: ``common_reference_t`` of ``reference_wrapper`` Should Be a Reference Type (`Github <https://github.com/llvm/llvm-project/issues/105260>`__)
-- P3168R2 Give ``std::optional`` Range Support (`Github <https://github.com/llvm/llvm-project/issues/105430>`__)
 
 Improvements and New Features
 -----------------------------

libcxx/docs/Status/Cxx2cPapers.csv

@@ -66,7 +66,7 @@
 "`P2747R2 <https://wg21.link/P2747R2>`__","``constexpr`` placement new","2024-06 (St. Louis)","|Complete|","20",""
 "`P2997R1 <https://wg21.link/P2997R1>`__","Removing the common reference requirement from the indirectly invocable concepts","2024-06 (St. Louis)","|Complete|","19","Implemented as a DR against C++20. (MSVC STL and libstdc++ will do the same.)"
 "`P2389R2 <https://wg21.link/P2389R2>`__","``dextents`` Index Type Parameter","2024-06 (St. Louis)","|Complete|","19",""
-"`P3168R2 <https://wg21.link/P3168R2>`__","Give ``std::optional`` Range Support","2024-06 (St. Louis)","|Complete|","21",""
+"`P3168R2 <https://wg21.link/P3168R2>`__","Give ``std::optional`` Range Support","2024-06 (St. Louis)","|Complete|","22",""
 "`P3217R0 <https://wg21.link/P3217R0>`__","Adjoints to 'Enabling list-initialization for algorithms': find_last","2024-06 (St. Louis)","","",""
 "`P2985R0 <https://wg21.link/P2985R0>`__","A type trait for detecting virtual base classes","2024-06 (St. Louis)","|Complete|","20",""
 "`P0843R14 <https://wg21.link/P0843R14>`__","``inplace_vector``","2024-06 (St. Louis)","","",""

libcxx/test/std/utilities/optional/iterator.pass.cpp

@@ -25,7 +25,6 @@
 #include <type_traits>
 
 #include "test_macros.h"
-#include "check_assertion.h"
 
 constexpr bool test_concepts() {
   const std::optional<char> opt{'a'};