[clang-tools-extra] reapply [clang-doc] Add --asset option to clang-doc (PR #96358)

[via cfe-commits]

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@@ -0,0 +1,2 @@
+// RUN: clang-doc --format=html --executor=standalone %s -output=%t/docs | FileCheck %s
+// CHECK: Using default asset: {{.*}}{{[\/]}}share{{[\/]}}clang
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PeterChou1 wrote:

I added a much more comprehensive test now I think

https://github.com/llvm/llvm-project/pull/96358