Extract Interface/Pull Up: Drop 'final' modifier when moving to an interface

#KT-15640 Fixed

idea/testData/refactoring/extractInterface/dropFinal.kt

@@ -0,0 +1,6 @@
+// NAME: I
+// SIBLING:
+class <caret>A {
+    // INFO: {checked: "true"}
+    final val one = 1
+}

idea/testData/refactoring/extractInterface/dropFinal.kt.after

@@ -0,0 +1,11 @@
+interface I {
+    // INFO: {checked: "true"}
+    val one: Int
+}
+
+// NAME: I
+// SIBLING:
+class A : I {
+    // INFO: {checked: "true"}
+    final override val one = 1
+}