Don't block on cache renewals, but notify library on updates so that the badges show up when ready.
We skip the cache when checking if a chapter is downloaded for the reader assuming that it's a
relatively low cost to check for a single chapter.
(Probably) fixes#8254 / fixes#7847
(cherry picked from commit 7e40680af02505f82fa3655d2d693092c6bd43a1)
# Conflicts:
# app/src/main/java/eu/kanade/tachiyomi/data/download/DownloadCache.kt
# app/src/main/java/eu/kanade/tachiyomi/extension/ExtensionManager.kt
# app/src/main/java/eu/kanade/tachiyomi/ui/reader/ReaderPresenter.kt
5a55c66532