Reformat Kotlin snippet in README (#781)

It now conforms to the official Kotlin style guide.

tutorials/Web/Getting_Started/README.md

@@ -103,14 +103,14 @@ fun main() {
     var count: Int by mutableStateOf(0)
 
     renderComposable(rootElementId = "root") {
-        Div({style { padding(25.px) }}) {
+        Div({ style { padding(25.px) } }) {
             Button(attrs = {
                 onClick { count -= 1 }
             }) {
                 Text("-")
             }
 
-            Span({style {padding(15.px) }}) {
+            Span({ style { padding(15.px) } }) {
                 Text("$count")
             }