Suspicious lit test output for function parameter

Need to check why `foo2` is broken. But autocomplete seems to work fine :thinking:

```
foo2(float a) vs   [incorrect?]
foo2(<#float a#>)  [expected?]
```

_Originally posted by @MythreyaK in https://github.com/llvm/llvm-project/pull/154041#discussion_r2281844547_
            