[llvm] [llvm][docs] Improve usage note on stacked PRs (PR #138949)

[Aiden Grossman via llvm-commits]

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@@ -288,16 +288,15 @@ Your options are as follows:
    in ``llvm/llvm-project``.
 
 .. note::
-   When not using user branches, GitHub will not display proper diffs for
+   When using the second approach, GitHub will not display proper diffs for
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boomanaiden154 wrote:

I would prefer to avoid numbering the approaches and just refer to them using a short name. I prefer the current state of this line rather than these changes.

https://github.com/llvm/llvm-project/pull/138949