add inlined schema()

Author: FelixEngl

kotlin-spark-api/2.4/src/main/kotlin/org/jetbrains/kotlinx/spark/api/ApiV1.kt

@@ -269,6 +269,9 @@ inline fun <reified R> Dataset<*>.toArray(): Array<R> = to<R>().collect() as Arr
  */
 fun <T> Dataset<T>.showDS(numRows: Int = 20, truncate: Boolean = true) = apply { show(numRows, truncate) }
 
+@OptIn(ExperimentalStdlibApi::class)
+inline fun <reified T> schema(map: Map<String, KType> = mapOf()) = schema(typeOf<T>(), map)
+
 @OptIn(ExperimentalStdlibApi::class)
 fun schema(type: KType, map: Map<String, KType> = mapOf()): DataType {
     val primitiveSchema = knownDataTypes[type.classifier]