[clang] [clang][docs] Add link to C++ modules Wikipedia page to docs (PR #169200)

[via cfe-commits]

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@@ -28,8 +28,11 @@ Standard C++ Named modules
 In order to better understand the compiler's behavior, it is helpful to
 understand some terms and definitions for readers who are not familiar with the
 C++ feature. This document is not a tutorial on C++; it only introduces
-necessary concepts to better understand use of modules in a project.
-
+necessary concepts to better understand use of modules in a project. Other 
+resources at `Wikipedia
+<https://en.cppreference.com/w/cpp/language/modules.html>`_ and `cppreference
+<https://en.wikipedia.org/wiki/Modules_(C++)>`_ can provide more background
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mikomikotaishi wrote:

Fixed it

https://github.com/llvm/llvm-project/pull/169200