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

[Daan De Meyer via cfe-commits]

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@@ -1647,7 +1647,7 @@ FormatStyle getLLVMStyle(FormatStyle::LanguageKind Language) {
   LLVMStyle.SeparateDefinitionBlocks = FormatStyle::SDS_Leave;
   LLVMStyle.ShortNamespaceLines = 1;
   LLVMStyle.SkipMacroDefinitionBody = false;
-  LLVMStyle.SortIncludes = {/*Enabled=*/true, /*IgnoreCase=*/false};
+  LLVMStyle.SortIncludes = {/*Enabled=*/true, /*IgnoreCase=*/false, /*IgnoreExtension=*/false};
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DaanDeMeyer wrote:

I'm very confused now what the suggestion is that I should apply here to make everyone happy

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