Update KotlinPoet to 1.3.0 (#915)

* Update to KotlinPoet 1.3.0

* Add hotwords test case

* Use %N for toJson parameter names to ensure escaping

kotlin/tests/src/test/kotlin/com/squareup/moshi/kotlin/codgen/GeneratedAdaptersTest.kt

@@ -1223,5 +1223,11 @@ data class SmokeTestType(
   val genericAlias: GenericTypeAlias = listOf("Woah")
 )
 
+// Compile only, regression test for https://github.com/square/moshi/issues/848
+@JsonClass(generateAdapter = true)
+data class Hotwords(
+    val `class`: List<String>?
+)
+
 typealias TypeAliasName = String
 typealias GenericTypeAlias = List<String>