Replace beego/orm with dbx (#2693)

* Start migration to dbx package

* Fix annotations and bookmarks bindings

* Fix tests

* Fix more tests

* Remove remaining references to beego/orm

* Add PostScanner/PostMapper interfaces

* Fix importing SmartPlaylists

* Renaming

* More renaming

* Fix artist DB mapping

* Fix playlist updates

* Remove bookmarks at the end of the test

* Remove remaining `orm` struct tags

* Fix user timestamps DB access

* Fix smart playlist evaluated_at DB access

* Fix search3

model/scrobble_buffer.go

@@ -5,7 +5,7 @@ import "time"
 type ScrobbleEntry struct {
 	MediaFile
 	Service     string
-	UserID      string `structs:"user_id" orm:"column(user_id)"`
+	UserID      string `structs:"user_id"`
 	PlayTime    time.Time
 	EnqueueTime time.Time
 }