JVM IR: Avoid direct invokes in callable reference tests

Due to the direct invoke optimization, most callable reference tests
were not generating callable references/lambdas.

compiler/testData/codegen/box/properties/kt2331.kt

@@ -3,7 +3,7 @@ class P {
         private set
 
     fun foo() {
-        ({ x = 4 })()
+        ({ x = 4 }).let { it() }
     }
 }