JetDiagnosticsTest migrated to TestGenerator

- test data files renamed from *.jet to *.kt

compiler/testData/diagnostics/tests/objects/kt2240.kt

@@ -0,0 +1,13 @@
+package a
+
+//KT-2240 Wrong overload resolution ambiguity when object literal is involved
+
+class A {}
+
+fun A.foo<T>(<!UNUSED_PARAMETER!>f<!> : T) {}
+
+val o = object {
+    fun foo<T>(f: T) {
+        A().foo(f) // Ambiguity here!
+    }
+}