Push Down: Support moving members from Java to Kotlin class

#KT-9485 Fixed

idea/testData/refactoring/pushDown/j2k/fromInterface.java

@@ -0,0 +1,12 @@
+interface <caret>I {
+    // INFO: {"checked": "true"}
+    int x = 2 * 3;
+
+    // INFO: {"checked": "true"}
+    int bar(String s);
+
+    // INFO: {"checked": "true"}
+    class X {
+
+    }
+}