[llvm] [Github] Fix revisions in code format action reproducers (PR #155193)

[Baranov Victor via llvm-commits]

================
@@ -92,6 +92,12 @@ def pr_comment_text_for_diff(self, diff: str) -> str:
 {self.instructions}
 ``````````
 
+:warning:
+The reproduction instructions above might return results for more than one PR
+a stack if you are using a stacked PR workflow. You can limit the results by
----------------
vbvictor wrote:

```suggestion
The reproduction instructions above might return results for more than one PR
in a stack if you are using a stacked PR workflow. You can limit the results by
```
Missed preposition?

https://github.com/llvm/llvm-project/pull/155193