[llvm] [llvm][docs] Reorder Stacked PR approaches in GitHub.rst (PR #138126)

[Paschalis Mpeis via llvm-commits]

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@@ -274,8 +264,25 @@ Your options are as follows:
 
    This approach allows GitHub to display clean, incremental diffs for each PR
    in the stack, making it much easier for reviewers to see what has changed at
-   each step. Once `feature_1` is merged, you can rebase and re-target
-   `feature_2` to `main`.
+   each step. Once `feature_1` is merged, GitHub would automatically rebase and
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paschalis-mpeis wrote:

Done, thanks!

https://github.com/llvm/llvm-project/pull/138126