Update libraries, some lints (#4099)

* Update some plugins

* Fix some miscellaneous lints

app/src/main/java/eu/kanade/tachiyomi/data/backup/AbstractBackupManager.kt

@@ -41,8 +41,8 @@ abstract class AbstractBackupManager(protected val context: Context) {
     internal fun restoreChapterFetchObservable(source: Source, manga: Manga, chapters: List<Chapter>): Observable<Pair<List<Chapter>, List<Chapter>>> {
         return source.fetchChapterList(manga)
             .map { syncChaptersWithSource(databaseHelper, it, manga, source) }
-            .doOnNext { pair ->
-                if (pair.first.isNotEmpty()) {
+            .doOnNext { (first) ->
+                if (first.isNotEmpty()) {
                     chapters.forEach { it.manga_id = manga.id }
                     updateChapters(chapters)
                 }

app/src/main/java/eu/kanade/tachiyomi/data/backup/AbstractBackupRestore.kt

@@ -11,7 +11,6 @@ import eu.kanade.tachiyomi.data.track.TrackManager
 import eu.kanade.tachiyomi.source.Source
 import eu.kanade.tachiyomi.util.chapter.NoChaptersException
 import kotlinx.coroutines.Job
-import okio.source
 import rx.Observable
 import uy.kohesive.injekt.injectLazy
 import java.io.File