PDFs should be read-only

## Description:
The filing outputs (PDFs) should be read-only/locked for editing, so that users cannot change the text and falsify the forms.

**Dependencies**
This depends on the PDF generator code.

**Acceptance Criteria**

**Validation Rules**

Ready to Build (DoR):
- [ ] Stakeholders have approved
- [ ] User story completed
- [ ] What are the dependencies
- [ ] Validation rules defined (UI, Data, Role-Action)
- [ ] Is a formal UAT required

Acceptance / DoD:
- [ ] Design / Solution accepted by Product Owner
- [ ] Acceptance criteria has been defined (happy path, known sad paths)
- [ ] Test coverage acceptable
- [ ] Peer Reviewed
- [ ] Accessibility reviewed and acceptable [checklist](https://github.com/bcgov/entity/docs/coding-standards/accessibility.md)
- [ ] UX Approved
- [ ] PR Accepted
- [ ] Production burn in completed