Add a --format json to the JFrog audit command

[Vinzz]

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

I'd like to get a json output of the JFrog audit commands I run. Vulnerabilities on the build output is neat, but a json file to puch to SonarQube would be way better.

Describe the solution you'd like to see
Ad a new text argument in the JFrogAudit@1 build task, it would be 'Format' and accept json or table as value

Describe alternatives you've considered
None I can think of yet