KT-50862 Unwrap use-site substitution overrides

Use-site substitution override happens in situations like this:

```
interface List<A> { fun get(i: Int): A }

fun take(list: List<String>) {
  list.get(10) // this call
}
```

We want to have those overrides unwrapped, because we don't want
to deal with a different KtSymbol for each possible use-site

^KT-50862 Fixed

analysis/analysis-api/testData/referenceResolve/arrayAccess/get.txt

@@ -1,2 +1,2 @@
 Resolved to:
-0: (in kotlin.collections.MutableList) operator fun get(index: kotlin.Int): kotlin.Int
+0: (in kotlin.collections.MutableList) operator fun get(index: kotlin.Int): E

analysis/analysis-api/testData/referenceResolve/arrayAccess/set.txt

@@ -1,2 +1,2 @@
 Resolved to:
-0: (in kotlin.collections.MutableList) operator fun set(index: kotlin.Int, element: kotlin.Int): kotlin.Int
+0: (in kotlin.collections.MutableList) operator fun set(index: kotlin.Int, element: E): E