[clang-tidy] [PR50069] readability-braces-around-statements doesn't work well...

[clang-tidy] [PR50069] readability-braces-around-statements doesn't work well with [[likely]] [[unlikely]]

https://bugs.llvm.org/show_bug.cgi?id=50069

When clang-tidy sees:

```
if (true) [[unlikely]] {
    ...
}
```

It thinks the braces are missing and add them again.

```
if (true)  { [[unlikely]] {
    ...
  }
}
```

This revision aims to prevent that incorrect code generation

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D105479