Allow configuration of YAML output format through config

[MarcEspiard]

Description

Adds an option to control the inline and indent of the yaml output through config

Motivation and context

Useful for readability of exported yaml file, especially during development of the api when you might not have a solution yet to display the docs in an actual frontend. It is also coherent with the json output format using the JSON_PRETTY_PRINT flag, this PR allows you to pretty print the YAML file if you wish to do so. It is backward compatible with default values not changing behavior for existing installs

How has this been tested?

Tested the output while changing config values, all works as expected

Screenshots (if appropriate)

Types of changes

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• [ ] Breaking change (fix or feature that would cause existing functionality to change)

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