Don't add new public APIs for Kotlin type inference

We can do a better job of this when we make the core Moshi module
depend on the Kotlin stdlib

kotlin/tests/src/test/kotlin/com/squareup/moshi/kotlin/reflect/-MoshiKotlinExtensions.kt

@@ -1,3 +1,18 @@
+/*
+ * Copyright (C) 2019 Square, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 package com.squareup.moshi.kotlin.reflect
 
 import com.squareup.moshi.JsonAdapter