add support for sarif

[dani-santos-code]

This idea was proposed by @thepwagner:

We could extend Kubeaudit to output results in Static Analysis Results Interchange Format (SARIF) format. This would allow integrating with GitHub via GitHub Code Scanning:

This means OSS users can use Kubeaudit on GitHub Actions - https://docs.github.com/en/code-security/code-scanning/integrating-with-code-scanning/uploading-a-sarif-file-to-github#example-workflow-that-runs-the-eslint-analysis-tool

ISSUE TYPE

• Bug Report
• Feature Idea

FEATURE IDEA

• If the maintainers agree with the feature as described here, I intend to submit a Pull Request myself.¹

Proposal:

¹ _{This is the quickest way to get a new feature! We reserve the right to close feature requests, even ones we like, if the proposer does not intend to contribute to the feature and it doesn't fit in our current roadmap.}