Big change in quickfix tests: no stupid test data format with "before" and "after" file prefixes

idea/testData/quickfix/createFromUsage/createClass/referenceExpression/enumEntryWithSuperclass.kt

@@ -0,0 +1,15 @@
+// "Create enum constant 'A'" "false"
+// ACTION: Convert to block body
+// ACTION: Create object 'A'
+// ERROR: Unresolved reference: A
+package p
+
+fun foo(): X = E.<caret>A
+
+enum class E {
+
+}
+
+open class X {
+
+}