Add ability to specify root security and securitySchemes components

[MarcEspiard]

Description

This PR adds the ability to specify securitySchemes and the root level security array from the config file

Motivation and context

Needed for our docs and in the project's TODO list

How has this been tested?

Added tests for generation, locally tested with and without config

Screenshots (if appropriate)

Types of changes

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

Checklist:

Go over all the following points, and put an x in all the boxes that apply.

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• [x] I have added tests to cover my changes.
• [x] If my change requires a change to the documentation, I have updated it accordingly.

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