Add ability to specify root security and securitySchemes components (Code style fixes)

[flofloflo]

I've used the stale PR #16 as base and did the last bit of code style fixes to make it ready for a merge. Style checks and tests are passing. I was also able to verify the functionality in a manual test as well.

If more changes are needed, I'm happy to help to get this ready for master.

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)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

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