[clang-tools-extra] [clang-doc] Add concepts to namespace template (PR #173956)

[Erick Velez via cfe-commits]

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@@ -1,5 +1,6 @@
 // RUN: rm -rf %t && mkdir -p %t
 // RUN: clang-doc --extra-arg -std=c++20 --output=%t --format=json --executor=standalone %s
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evelez7 wrote:

Good catch, thanks.

https://github.com/llvm/llvm-project/pull/173956