[llvm] [Github] Escape `@` and html in the <details> block (PR #66118)

[Mehdi Amini via llvm-commits]

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@@ -113,6 +122,11 @@ def run(self) -> bool:
             print(f"couldn't find team named {self.team_name}")
             return False
 
+        # GitHub limits comments to 65,536 characters, let's limit the diff
+        # and the file list to 20kB each.
+        STAT_LIMIT = 20 * 1024
+        DIFF_LIMIT = 20 * 1024
+
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joker-eph wrote:

This isn't in the PR description, can you add it there? (with some context for the "why" of the change)

https://github.com/llvm/llvm-project/pull/66118