Get rid of duplicate code

src/libdanbooru/servicebase.h

@@ -77,18 +77,8 @@ protected:
 
 public:
 
-
-enum ApiType {
-    OriginalDanbooru = 16,
-    MoeBooru = 32,
-    Gelbooru = 64,
-    Unknown = 128
-    };
-
-Q_DECLARE_FLAGS(ApiTypes, DanbooruServiceBase::ApiType)
-
     explicit DanbooruServiceBase(QUrl boardUrl = QUrl(), QObject* parent=nullptr);
-    virtual ~DanbooruServiceBase();
+    virtual ~DanbooruServiceBase() = default;
 
     /////////////////////////////////////////////
     // Functions shared with all implementations