[clang] [Format] Fix isStartOfName to recognize attributes (PR #76804)

[Ilya Biryukov via cfe-commits]

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@@ -1698,8 +1698,6 @@ FormatStyle getGoogleStyle(FormatStyle::LanguageKind Language) {
           /*BasedOnStyle=*/"google",
       },
   };
-  GoogleStyle.AttributeMacros.push_back("GUARDED_BY");
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ilya-biryukov wrote:

@HazardyKnusperkeks friendly ping. Any thoughts on including a few more attributes into the (the first list of 4 elements) vs landing this change and relying on implicit formatting of those as function names?

I am happy to choose one of the two options arbitrarily, but I don't have enough context on `clang-format` to understand which approach is preferable, so I would love to get an opinion from someone in the `clang-format` community.

https://github.com/llvm/llvm-project/pull/76804