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

[Owen Pan via cfe-commits]

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@@ -8498,9 +8498,6 @@ TEST_F(FormatTest, BreaksFunctionDeclarationsWithTrailingTokens) {
                "    __attribute__((unused));");
 
   Style = getGoogleStyle();
-  ASSERT_THAT(Style.AttributeMacros,
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owenca wrote:

Please also delete line 10:
```
#include "gmock/gmock.h"
```

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