update user details

### Feature 2: Update User
#### User story
User can update their profile.
#### Pre-requisites:
- Implements User Service(update(int id, User user))
- Implement User DAO(update(int id, User user))
- User table

#### Validation
- [ ] Form validation
- id <=0
- user null check
- name (null or empty string)
- email (null or empty string)
- password (null or empty string)
- phone_number ( length, >= 600000001 && <= 9999999999 )
- [ ] Business validation
- Check whether id is in the table or not

#### Messages
- [ ] User cannot be null
- [ ] name cannot be null or empty
- [ ] email cannot be null or empty
- [ ] password cannot be null or empty
- [ ] Invalid Email Id
- [ ] Password doesn't match the required format
- [ ] phone_number doesn't match the required format
- [ ] User Id not found(Business validation)

#### Flow:
```mermaid
graph TD;
A["User Service: User Update "] -->
B["Form Validation"]
B -- Valid --> C0["Business Validation"]
C0 --> C["Whether the ID is in the database or not"]
B -- InValid --> C1["Invalid input"]
C -- Yes --> D["User DAO: Update User"]
D --> E["User Service: User Updated(Response)"]
C -- No --> F["Validation Exception: User not found for the given ID (Error Response)"]
```