[FIR] Unwrap definitely not null when matching overrides

#KT-41984 Fixed

compiler/fir/analysis-tests/testData/resolve/kt41984.kt

@@ -0,0 +1,31 @@
+// ISSUE: KT-41984
+
+// FILE: A.java
+
+import org.jetbrains.annotations.NotNull;
+
+public abstract class A<T, V> {
+    @NotNull
+    public abstract String take(@NotNull V value);
+
+    @NotNull
+    public abstract String takeInv(@NotNull Inv<@NotNull V> value);
+}
+
+// FILE: main.kt
+
+class Inv<T>
+
+open class B<V> : A<Any, V>() {
+    override fun take(value: V): String {
+        return ""
+    }
+
+    override fun takeInv(value: Inv<V>): String = ""
+}
+
+fun test_1(b: B<Int>, x: Int, inv: Inv<Int>) {
+    b.take(x)
+    b.<!INAPPLICABLE_CANDIDATE!>take<!>(null)
+    b.takeInv(inv)
+}