Delete existing download of new chapters

The downloader checks if pages are already downloaded to prevent unnecessary downloads.
However, in case this is e.g. a re-uploaded chapter, this will prevent the new pages from getting downloaded

server/src/main/kotlin/suwayomi/tachidesk/manga/impl/Chapter.kt

@@ -377,6 +377,10 @@ object Chapter {
             return
         }
 
+        // the download logic checks if a page is already downloaded, by deleting existing downloads, it's ensured that
+        // this is not possible and prevents the new pages from getting downloaded
+        deleteChapters(chapterIdsToDownload)
+
         log.info { "download ${chapterIdsToDownload.size} new chapter(s)..." }
 
         DownloadManager.enqueue(EnqueueInput(chapterIdsToDownload))