[clang] clang-format: Add IncludeSortKey option (PR #137840)

[Björn Schäpers via cfe-commits]

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@@ -4226,6 +4226,19 @@ the configuration (without a prefix: ``Auto``).
   ``ClassImpl.hpp`` would not have the main include file put on top
   before any other include.
 
+.. _IncludeSortKey:
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HazardyKnusperkeks wrote:

Did you write this on your own? You need to do that in `IncludeStyle.h` and run `clang/docs/tools/dump_format_style.py`.

https://github.com/llvm/llvm-project/pull/137840