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

idea/testData/quickfix/createFromUsage/createClass/callExpression/callInMemberVarDelegateRuntime.kt

@@ -0,0 +1,8 @@
+// "Create class 'Foo'" "true"
+// DISABLE-ERRORS
+
+open class B
+
+class A<T>(val t: T) {
+    var x: B by <caret>Foo(t, "")
+}