fix compilation

Author: oshai

src/wasmJsMain/kotlin/io/github/oshai/kotlinlogging/KotlinLoggingConfiguration.kt

@@ -1,23 +1,21 @@
 package io.github.oshai.kotlinlogging
 
-private val startupMessageDisabledInWindow: Boolean =
+private fun startupMessageDisabledInWindow(): Boolean =
   js(
     "typeof window !== 'undefined' && (window.KOTLIN_LOGGING_STARTUP_MESSAGE === 'false' || window.KOTLIN_LOGGING_STARTUP_MESSAGE === false)"
   )
-    as Boolean
 
-private val startupMessageDisabledInEnv: Boolean =
+private fun startupMessageDisabledInEnv(): Boolean =
   js(
     "typeof process !== 'undefined' && process.env && (process.env.KOTLIN_LOGGING_STARTUP_MESSAGE === 'false' || process.env.KOTLIN_LOGGING_STARTUP_MESSAGE === false)"
   )
-    as Boolean
 
 private fun resolveStartupMessageDefault(): Boolean {
   try {
-    if (startupMessageDisabledInWindow) {
+    if (startupMessageDisabledInWindow()) {
       return false
     }
-    if (startupMessageDisabledInEnv) {
+    if (startupMessageDisabledInEnv()) {
       return false
     }
     return true