Extraction Engine: Generate function/property accessor with expression body (whenever applicable)

#KT-6405 Fixed

idea/testData/refactoring/extractFunction/defaultContainer/localFunction.kt.after

@@ -1,7 +1,5 @@
 fun foo(a: Int, b: Int): Int {
-    fun i(): Int {
-        return a + b - 1
-    }
+    fun i() = a + b - 1
 
     fun bar() {
         return i()