Fix use of platform type for contextName
diff --git a/log4j-api-kotlin/src/main/kotlin/org/apache/logging/log4j/kotlin/LoggingFactory.kt b/log4j-api-kotlin/src/main/kotlin/org/apache/logging/log4j/kotlin/LoggingFactory.kt
index 5548476..7488bf6 100644
--- a/log4j-api-kotlin/src/main/kotlin/org/apache/logging/log4j/kotlin/LoggingFactory.kt
+++ b/log4j-api-kotlin/src/main/kotlin/org/apache/logging/log4j/kotlin/LoggingFactory.kt
@@ -45,7 +45,7 @@
  * @param context should always be `{}`
  * @return normalized context name
  */
-fun contextName(context: () -> Unit) = with(context::class.java.name) {
+fun contextName(context: () -> Unit): String = with(context::class.java.name) {
   when {
     contains("Kt$") -> substringBefore("Kt$")
     contains("$") -> substringBefore("$")