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

[Paschalis Mpeis via llvm-commits]

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@@ -288,13 +288,13 @@ Your options are as follows:
    in ``llvm/llvm-project``.
 
 .. note::
-   When not using user branches, GitHub will not display proper diffs for
-   subsequent PRs in a stack. Instead, it will show a combined diff that
-   includes all commits from earlier PRs.
+   When using the dependency notes approach, GitHub will not display proper
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paschalis-mpeis wrote:

Hey Andrzej,

Thanks for the review! Just to share my thinking:
I was aiming to avoid the negative form ('not'), which also implicitly covered the 3rd-party tools case.
But I assume it's already clear to authors/reviewers that they'll ignore the GH render and use an external diff tool.

That said, I see your point: referring to 'user branches' is clearer and might also encourage that approach, which I'd personally prefer.

---

Changing docs can often be tricky. Even if I had a strong opinion, I'd still go with what most reviewers agrees on; that's usually what's best for the reader. Because of this I don't have a strong opinion and I'm very open to suggestions.

I'm happy to go with the phrase: `not using user branches` as suggested
I'll give it a day or two just in case some other view comes before pushing the patch.


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