bugFix: Job post column errors

Description

This PR addresses issues with the Job post column model, fixing errors that were causing incorrect data handling and storage. The changes ensure that the columns in the Job post model are correctly defined and aligned with the database schema, preventing runtime errors and improving data integrity.

Details of the Fix:

Corrected the column definitions in the Job post model to match the database schema.
Resolved issues with data types and constraints that were causing errors during data insertion and retrieval.

Related Issue (Link to Github issue)

No related issue

How Has This Been Tested?

The changes were tested by running the application locally with a variety of Job post data to ensure that the model correctly maps to the database columns. Unit tests were also updated to cover scenarios that previously caused errors.

Screenshots (if appropriate - Postman, etc):

Types of changes

[x] Bug fix (non-breaking change which fixes an issue)
[ ] New feature (non-breaking change which adds functionality)
[ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

[x] My code follows the code style of this project.
[x] I have updated the documentation accordingly.
[x] I have added tests to cover my changes.
[x] All new and existing tests passed.

hngprojects / hng_boilerplate_golang_web