[FIR-TEST] Add new testdata generated after changes in previous commit

compiler/testData/diagnostics/tests/annotations/kt1860-negative.fir.kt

@@ -0,0 +1,10 @@
+// !WITH_NEW_INFERENCE
+fun foo(@varargs f : Int) {}
+
+var bar : Int = 1
+  set(@varargs v) {}
+
+val x : (Int) -> Int = {@varargs x <!SYNTAX!>: Int -> x<!>}
+
+class Hello(@varargs args: Any) {
+}