Add validation to weekly working hour field in user tab

[nihal467]

Describe the bug

the weekly working hour field for in user tab accept empty entry upon clicking update button

To Reproduce
Steps to reproduce the behavior:

1. Go to https://care.ohc.network/users?page=1&limit=18&username=
2. Click on set work hour button
3. submit a empty form
4. See error

Expected behavior

Add a validation to verify the field has a value before submitting the form

Screenshots