Fix intentions tests after types enhancement

Types became more accurate

idea/testData/refactoring/extractFunction/controlFlow/returnTypeCandidates/javaAnnotatedNotNull.kt.after

@@ -4,4 +4,4 @@ fun test() {
     val s = s()
 }
 
-private fun s(): String = J.notNull()
+private fun s() = J.notNull()

idea/testData/refactoring/extractFunction/controlFlow/returnTypeCandidates/javaAnnotatedNullable.kt.after

@@ -3,4 +3,4 @@ fun test() {
     val s = s()
 }
 
-private fun s(): String? = J.nullable()
+private fun s() = J.nullable()