[SAM with receiver] Partially migrate tests to new infrastructure

Script tests still use old infrastructure, because there is no support
  for them in new framework

plugins/sam-with-receiver/testData/diagnostics/samConversionNoParameters.kt

@@ -1,4 +1,4 @@
-// !DIAGNOSTICS: -UNUSED_PARAMETER,-UNUSED_VARIABLE
+// FIR_IDENTICAL
 
 // FILE: Sam.java
 @SamWithReceiver
@@ -25,4 +25,4 @@ fun test() {
         val a: String = <!NO_THIS!>this<!>
         System.out.println(a)
     }
-}
+}