Prevent adding duplicated extensions to the db table

There is a possibility that multiple extension repos have been added which contain the same extensions.
In case these extensions have not been added to the db table yet, they would all get added to the db, which would create duplicated extensions

server/src/main/kotlin/suwayomi/tachidesk/manga/impl/extension/ExtensionsList.kt

@@ -83,16 +83,17 @@ object ExtensionsList {
 
     private fun updateExtensionDatabase(foundExtensions: List<OnlineExtension>) {
         transaction {
+            val uniqueExtensions = foundExtensions.distinctBy { it.pkgName }
             val installedExtensions =
                 ExtensionTable.selectAll().toList()
                     .associateBy { it[ExtensionTable.pkgName] }
             val extensionsToUpdate = mutableListOf<Pair<OnlineExtension, ResultRow>>()
             val extensionsToInsert = mutableListOf<OnlineExtension>()
             val extensionsToDelete =
                 installedExtensions.filter { it.value[ExtensionTable.repo] != null }.mapNotNull { (pkgName, extension) ->
-                    extension.takeUnless { foundExtensions.any { it.pkgName == pkgName } }
+                    extension.takeUnless { uniqueExtensions.any { it.pkgName == pkgName } }
                 }
-            foundExtensions.forEach {
+            uniqueExtensions.forEach {
                 val extension = installedExtensions[it.pkgName]
                 if (extension != null) {
                     extensionsToUpdate.add(it to extension)