public void Branch_Add_Book_Stock_Successfully()
{
Branch testBranch = new Branch("Test", 2);
var bookId = Guid.NewGuid();
testBranch.AddBookInventory(new BookInventory(bookId, 1, 1));
testBranch.AddBookStock(bookId);
testBranch.BookInventory.Should().HaveCount(1);
testBranch.BookInventory.First(x => x.BookId == bookId).Total.Should().Be(2);
testBranch.BookInventory.First(x => x.BookId == bookId).TotalInStock.Should().Be(2);
}
