Add option to remove non library mangas from categories (#520)

It's currently not possible to filter out non library mangas from the mangas field of categories, thus, the totalCount of mangas in a category might be greater than what is actually displayed in the library.

src/lib/requests/RequestManager.ts

@@ -1341,6 +1341,13 @@ export class RequestManager {
         return this.doRequest(GQLMethod.USE_QUERY, GET_MANGAS, variables, options);
     }
 
+    public getMangas(
+        variables: GetMangasQueryVariables,
+        options?: QueryOptions<GetMangasQueryVariables, GetMangasQuery>,
+    ): AbortabaleApolloQueryResponse<GetMangasQuery> {
+        return this.doRequest(GQLMethod.QUERY, GET_MANGAS, variables, options);
+    }
+
     public getMangaThumbnailUrl(mangaId: number): string {
         return this.getValidImgUrlFor(`manga/${mangaId}/thumbnail`);
     }