Remove API_VERSION 1.3 from tests on JvmDefault

So that these tests will now check behavior on the latest API version

compiler/testData/codegen/box/jvm8/defaults/oneImplementation.kt

@@ -1,4 +1,3 @@
-// !API_VERSION: 1.3
 // !JVM_DEFAULT_MODE: enable
 // TARGET_BACKEND: JVM
 // JVM_TARGET: 1.8
@@ -23,4 +22,4 @@ open class KMutableProperty1Impl : KProperty1Impl(), KCallable
 
 fun box(): String {
     return KMutableProperty1Impl().returnType
-}
+}