[Tests] Add missing diagnostics handler to irText tests

Merge-request: KT-MR-11721
Merged-by: Vladimir Sukharev <Vladimir.Sukharev@jetbrains.com>

compiler/testData/ir/irText/errors/unresolvedReference.kt

@@ -2,6 +2,7 @@
 // IGNORE_BACKEND: JS_IR
 // IGNORE_BACKEND: JS_IR_ES6
 // !IGNORE_ERRORS
+// DIAGNOSTICS: -UNRESOLVED_REFERENCE -OVERLOAD_RESOLUTION_AMBIGUITY
 
 val test1 = unresolved
 
@@ -10,4 +11,4 @@ val test2: Unresolved =
 
 val test3 = 42.unresolved(56)
 
-val test4 = 42 *
+val test4 = 42 *<!SYNTAX!><!>