[clang-format] Finalize children after formatting them (#73753)

This would also fix the overlapping replacements below:
```
$ clang-format
 a(
 #else
 #endif
) = []() {      
)}
The new replacement overlaps with an existing replacement.
New replacement: <stdin>: 38:+7:"
"
Existing replacement: <stdin>: 38:+7:" "
```
Fixed #73487.