Book Module | Update Book Feature

# Updating Book Process

### User Story
As a librarian, I want to be able to update information about books in the library's collection. This includes updating details such as book titles, authors, genres, and availability statuses. When I identify a book that requires an update, I should be able to modify the relevant information and save the changes. If the book I'm looking for is not found, the system should display a message indicating that the book is not available for updating.

### Task

- [x] Implement Data Access Object (DAO) Layer.
- [x] Implement Service Layer.
- [x] Create JUnit Test Cases.
- [x] Ensure that the tests cases are passing.
- [x] Write clear and concise comments in the code to explain complex logic.

#### DAO
- updateBook()

#### Service
- updateBook()

#### Junit Test
- testValidUpdateBook()
- testInvalidUpdateBook()

### Estimation
- 3 hours

# Flowchart

```mermaid
graph TD
A[[Start]] --> B([Librarian Initiates Update Book])
B --> C[(Search Book to Update)]
C --> |Book Not Found| D{{Service Exception}}
D --> |Fail| E([Failed to Update Book])
C --> |Book Found| G([Update Book Details])
G --> |Save Changes| F([Book Updated Successfully!])
E --> I[[End]]
F --> |Returns Book| I

style F fill:#dfd,stroke:#333
style E fill:#fdd,stroke:#333