enclosingSourceSymbols returns parent symbol for pattern matches

## Compiler version

3.0.0-RC1

## Minimized code

```Scala
object A:
  val (fir@@st, second) = (1, 2)
```

When using `Interactive.enclosingSourceSymbols` for the position at `@@` we get symbol for the object A.

## Output

This results in Metals showing
```scala
object A: (Int, Boolean)
```

## Expectation

```scala
first: Int
```