utoon: fix NPE on chapter list (#4643)

src/en/utoon/build.gradle

@@ -3,7 +3,7 @@ ext {
     extClass = '.Utoon'
     themePkg = 'madara'
     baseUrl = 'https://utoon.net'
-    overrideVersionCode = 1
+    overrideVersionCode = 2
 }
 
 apply from: "$rootDir/common.gradle"

src/en/utoon/src/eu/kanade/tachiyomi/extension/en/utoon/Utoon.kt

@@ -19,8 +19,6 @@ class Utoon : Madara(
 
     override fun chapterListSelector() = "li.wp-manga-chapter:not(.premium-block)"
 
-    override val chapterUrlSelector = "div > a"
-
     override fun chapterFromElement(element: Element): SChapter {
         return super.chapterFromElement(element).apply {
             val currentYear = Calendar.getInstance().get(Calendar.YEAR)