[clangd] don't add inlay hint for dependent type in structured binding

Currently clangd will display useless inlay hint for dependent type in
structured binding, e.g.

```
template <class T>
void foobar(T arg) {
  auto [a/*: <dependent type>*/, b/*: <dependent type>*/] = arg;
}
```

Differential Revision: https://reviews.llvm.org/D157956