[clang] [llvm] [docs] Replace clang.llvm.org/docs links with Sphinx links (PR #222507)

[Reid Kleckner via llvm-commits]

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@@ -598,7 +598,7 @@ By default, the following summaries are assumed:
   including the implicit `this` parameter.
 
 These summaries can be overriden with the following
-[attributes](https://clang.llvm.org/docs/AttributeReference.html#os-returns-not-retained):
+{ref}`attributes <os-retained-attr-family>`:
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rnk wrote:

This is a notable exception to the style guide because it doesn't refer to a section, it refers to a specific paragraph in the attribute reference documentation. At least, that's what I *think* this should refer to. The LHS link anchor is broken, so I'm guessing.

https://github.com/llvm/llvm-project/pull/222507