Adding SARIF result format support for speccy

[shaopeng-gh]

Detailed description

Hello! We are interested in adding support for output in the open-standard SARIF format to speccy. SARIF support is required to integrate it in GitHub code scanning. Doing so would make it available to every repo in GitHub and could result in increase in user base.

You can learn more about SARIF here:
What is SARIF?
Why SARIF?

We have made the code changes: #481 , please kindly review and let me know.
After the support for SARIF output is added to the tool, we will work on creating a starter workflow to make it available as a GitHub code scanner.

Thanks,
Shaopeng