[clang] [clang-format] Fix annotating attrs in class/struct (PR #124634)

[Björn Schäpers via cfe-commits]

HazardyKnusperkeks wrote:

> (Why drop the formatting test? Seems good to have an integration test for this, no?)

Because the bug was a misannotation. The formatting, based on the annotations, should already be covered. Of course one can always add more tests, and I'm not demanding to remove it, I simply suggest it. The more test cases there are, the longer the duration of building and running the tests for all (clang-format) developers and CIs.

https://github.com/llvm/llvm-project/pull/124634