Add config file support for existing parameters

[adhilto]

🗣 Description

Added config file support for the existing ScubaGoggles parameters. See https://github.com/cisagov/ScubaGoggles/blob/403-add-config-file-support-for-existing-parameters/docs/usage/Config.md for usage details.

💭 Motivation and context

Closes #403.

🧪 Testing

Note this adds a new dependency: pyyaml. Be sure to install that before testing.

Manually tested:

• Ran without config file
• Tested with config file
• Tested with parameters in both config file and specified in the command-line
• Tested with a mix of both full parameter names and aliases (i.e., -b vs --baselines)

✅ Pre-approval checklist

• This PR has an informative and human-readable title.
• Changes are limited to a single goal - eschew scope creep!
• If applicable, All future TODOs are captured in issues, which are referenced in the PR description.
• The relevant issues PR resolves are linked preferably via closing keywords.
• All relevant type-of-change labels have been added.
• I have read and agree to the CONTRIBUTING.md document.
• These code changes follow cisagov code standards.
• All relevant repo and/or project documentation has been updated to reflect the changes in this PR.
• Tests have been added and/or modified to cover the changes in this PR.
• All new and existing tests pass.

✅ Pre-merge Checklist

• This PR has been smoke tested to ensure main is in a functional state when this PR is merged.
• Squash all commits into one PR level commit using the Squash and merge button.

✅ Post-merge Checklist

• Delete the branch to clean up.
• Close issues resolved by this PR if the closing keywords did not activate.

[mitchelbaker-cisa]

Looks good, Tested with/without a config file when run via scubagoggles gws and scuba.py. Tested with parameters in both config file/command-line, and with a mix of full param names/aliases.

Left one comment for consideration.

[LaurenBassett]

Tests ran fine for me :-)