Properly process chapters without a group name (#8785)

* Fixed MangaDex content rating preferences being swapped

* Properly process anonymous chapters

* Remembered to account for empty string

src/all/mangadex/build.gradle

@@ -6,7 +6,7 @@ ext {
     extName = 'MangaDex'
     pkgNameSuffix = 'all.mangadex'
     extClass = '.MangaDexFactory'
-    extVersionCode = 128
+    extVersionCode = 129
     libVersion = '1.2'
     containsNsfw = true
 }

src/all/mangadex/src/eu/kanade/tachiyomi/extension/all/mangadex/MangaDexHelper.kt

@@ -260,6 +260,8 @@ class MangaDexHelper() {
                 )
             }.mapNotNull { it.attributes!!.name }
                 .joinToString(" & ")
+                .replace("no group", "No Group")
+                .ifEmpty { "No Group" }
 
             val chapterName = mutableListOf<String>()
             // Build chapter name
@@ -289,6 +291,7 @@ class MangaDexHelper() {
             if (chapterName.isEmpty()) {
                 chapterName.add("Oneshot")
             }
+
             // In future calculate [END] if non mvp api doesnt provide it
 
             return SChapter.create().apply {