[llvm] [clang-tools-extra] [clang] [clang] Add test for CWG472 (PR #67948)

[Vlad Serebrennikov via cfe-commits]

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@@ -2871,7 +2871,7 @@ <h2 id="cxxdr">C++ defect report implementation status</h2>
     <td><a href="https://cplusplus.github.io/CWG/issues/472.html">472</a></td>
     <td>drafting</td>
     <td>Casting across protected inheritance</td>
-    <td align="center">Not resolved</td>
+    <td class="none" align="center">No</td>
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Endilll wrote:

Current state of things is my fault (I was the one who introduced `no open`, `no drafting`, and `no review` statuses). I've been pondering on a different idea recently: `No*`, and a pop-up saying something along the lines of `Tentative; issue hasn't been resolved yet`. Like cppreference does in their compiler support table. Seems less heavy for such a big table, but still provides details for those who are interested.

Another idea is for `No` to be a link to an issue on bug tracker instead of a pop-up.

It also worth mentioning that `make_cxx_dr_status` is strict with those unresolved statuses, and it yells every time status in a test doesn't match status in `cwg_index.html`.

https://github.com/llvm/llvm-project/pull/67948