[NI] Capture from supertypes of type parameter.

This works by accident in OI, so this should be supported by new inference.

compiler/testData/diagnostics/tests/inference/capturedTypes/captureFromTypeParameterUpperBound.kt

@@ -0,0 +1,11 @@
+interface Inv<T>
+
+fun <Y: X, X : Inv<out String>> foo(x: X, y: Y) {
+    val rX = bar(x)
+    rX.length
+
+    val rY = bar(y)
+    rY.length
+}
+
+fun <Y> bar(<!UNUSED_PARAMETER!>l<!>: Inv<Y>): Y = TODO()

compiler/testData/diagnostics/tests/inference/capturedTypes/captureFromTypeParameterUpperBound.txt

@@ -0,0 +1,10 @@
+package
+
+public fun </*0*/ Y> bar(/*0*/ l: Inv<Y>): Y
+public fun </*0*/ Y : X, /*1*/ X : Inv<out kotlin.String>> foo(/*0*/ x: X, /*1*/ y: Y): kotlin.Unit
+
+public interface Inv</*0*/ T> {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}