[clang-tools-extra] Follow style configuration in clangd when inserting missing includes (PR #140594)

[Nathan Ridge via cfe-commits]

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@@ -262,6 +264,8 @@ TEST(IncludeCleaner, GenerateMissingHeaderDiags) {
   TU.Filename = "main.cpp";
   TU.AdditionalFiles["a.h"] = guard("#include \"b.h\"");
   TU.AdditionalFiles["b.h"] = guard("void b();");
+  TU.AdditionalFiles["a_angled.h"] = guard("#include \"b_angled.h\"");
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HighCommander4 wrote:

 * if `a_angled.h` is not part of the `Angled` filter, it should probably be called `a_quoted.h` (or `c.h` or something else that doesn't include "angled")
 * to avoid confusion, let's make the include style of `b_angled.h` angled here in the contents of `a_angled.h` as well

https://github.com/llvm/llvm-project/pull/140594