[Serialization] Migrate all tests to new test infrastructure

plugins/kotlinx-serialization/testData/codegen/Basic.kt

@@ -1,4 +1,4 @@
-// CURIOUS_ABOUT serialize, deserialize, write$Self, childSerializers, <init>, <clinit>, getDescriptor
+// CURIOUS_ABOUT: serialize, deserialize, write$Self, childSerializers, <init>, <clinit>, getDescriptor
 // WITH_STDLIB
 
 import kotlinx.serialization.*
@@ -10,4 +10,4 @@ class User(val firstName: String, val lastName: String)
 class OptionalUser(val user: User = User("", ""))
 
 @Serializable
-class ListOfUsers(val list: List<User>)
+class ListOfUsers(val list: List<User>)

plugins/kotlinx-serialization/testData/codegen/Delegated.kt

@@ -1,4 +1,4 @@
-// CURIOUS_ABOUT <init>, <clinit>
+// CURIOUS_ABOUT: <init>, <clinit>
 // WITH_STDLIB
 
 import kotlinx.serialization.*
@@ -10,4 +10,4 @@ fun interface A {
 fun generateImpl() = A { "Hello, world!" }
 
 @Serializable
-class Test : A by generateImpl()
+class Test : A by generateImpl()

plugins/kotlinx-serialization/testData/codegen/Sealed.kt

@@ -1,4 +1,4 @@
-// CURIOUS_ABOUT deserialize, write$Self, childSerializers, <init>, <clinit>, invoke, serializer
+// CURIOUS_ABOUT: deserialize, write$Self, childSerializers, <init>, <clinit>, invoke, serializer
 // WITH_STDLIB
 
 import kotlinx.serialization.*
@@ -16,4 +16,4 @@ sealed class Result: X {
 }
 
 @Serializable
-class Container(val r: Result)
+class Container(val r: Result)