[clang] clang: add test for C2y n3605 (PR #178479)

[Aaron Ballman via cfe-commits]

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@@ -354,7 +354,7 @@ <h2 id="c2y">C2y implementation status</h2>
     <tr>
       <td>Generic replacement (v. 2 of quasi-literals)</td>
       <td><a href="https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3605.pdf">N3605</a></td>
-      <td class="unknown" align="center">Unknown</td>
+      <td class="full" align="center">Yes</td>
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AaronBallman wrote:

Naw, that's not enough of a difference to really matter, so I think what you've got here is great. Thank you!

https://github.com/llvm/llvm-project/pull/178479