Enhance validation process in the system

[mlab817]

Is your feature request related to a problem? Please describe.

• [ ] Only allow the reviewer to complete validation of PAP if the PAP has been SUBMITTED
• [ ] Disable editing of PAPs once validation is completed
• [ ] Allow completed validation to be reversed given that Tech Com may still have comments on the PAPs

Describe the solution you'd like N/A

Describe alternatives you've considered N/A

Additional context N/A