public async Task RemoveNotExistingBookFromShelf()
            {
                var shelf  = "read";
                var bookId = 1;
                var result = await ShelvesEndpoint.AddBookToShelf(shelf, bookId, "remove");

                Assert.False(result);
            }
            public async Task AddBookToShelf()
            {
                var shelf  = "to-read";
                var bookId = 7235533;
                var result = await ShelvesEndpoint.AddBookToShelf(shelf, bookId);

                Assert.True(result);
            }