Tools command to convert oscal between json/yaml

[brandtkeller]

Is your feature request related to a problem? Please describe.

Creation of a tools command to convert a given oscal file from one format to another (yaml/json)

Describe the solution you'd like

• Given a yaml oscal file exists
• When tools convert is executed
• Then a json file with identical contents is created

Describe alternatives you've considered

Compose can likely do this to-date - but there may still be value in conversion separate from compose.

Additional context

Thinking about future data sources that would benefit from easy conversion to json for experimentation purposes.