[RFE] Allow dynamic generation of IMDS responses

## Current situation
JSON responses are copied to a few separate locations and have a level of duplication that can be improved upon.

## Impact
This would reduce the duplication of JSON response files we have across the repo.

## Ideal future situation
We are able to generate files on command with a high degree of specificity for things like adminUsername, computerName, passwordAuthentication, and more.
We could also specify whether or not these files contained the fields at all to test azure-init's ability to handle bad IMDS responses.

## Additional information
It might be beneficial to store the extended data as a JSON file. At this point, sections of the json can be updated or removed as needed. The non extended JSON response can also cut out the info it needs to.