Add CSP rules to support redocs rendering

[jujaga]

Description

The addition of Helmet broke the ability to render the OpenAPI page. This commit fixes this by ensuring the required CSP rules are added in. This also applies a critical npm audit security fix.

Types of changes

Bug fix (non-breaking change which fixes an issue)

Checklist

• [x] I have read the CONTRIBUTING doc
• [x] I have checked that unit tests pass locally with my changes
• [x] I have added tests that prove my fix is effective or that my feature works
• [x] I have added necessary documentation (if appropriate)

Further comments

[codeclimate[bot]]

Code Climate has analyzed commit f5aabdbb and detected 0 issues on this pull request.

The test coverage on the diff in this pull request is 100.0% (50% is the threshold).

This pull request will bring the total coverage in the repository to 65.8% (0.0% change).

View more on Code Climate.

[github-actions[bot]]

Coverage Report

Totals
Statements:	59.23% ( 2737 / 4621 )
Methods:	49.21% ( 310 / 630 )
Lines:	65.81% ( 1646 / 2501 )
Branches:	52.42% ( 781 / 1490 )