[clang] [clang-format] Add FilesBeforeFolders option to SortIncludes (PR #208954)

[Savvas Shiakas via cfe-commits]

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@@ -6821,6 +6821,19 @@ the configuration (without a prefix: ``Auto``).
        # include "A.inc"              # include "A.h"
        # include "A-util.h"           # include "A.inc"
 
+  * ``bool FilesBeforeFolders`` When ``true``, sort includes so that files in a directory appear
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Shiakaron wrote:

Just copying my response from https://github.com/llvm/llvm-project/pull/208954#issuecomment-5153407438

> I've added a UT to cover this. When false all angle bracket includes go after quotes simply because " < <. When true this can change because now we first check that files go before folders. So <alpha.hpp> will go before "beta/x.hpp".

https://github.com/llvm/llvm-project/pull/208954