[clang] [clang-format] Add MainIncludeChar option. (PR #78752)

[Björn Schäpers via cfe-commits]

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@@ -3392,6 +3392,24 @@ the configuration (without a prefix: ``Auto``).
         Priority:        1
         SortPriority:    0
 
+.. _MainIncludeChar:
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HazardyKnusperkeks wrote:

Did you add this by hand? I'm wondering why it has a different order than in the header.

https://github.com/llvm/llvm-project/pull/78752