Fuzzing on forks

[kbuaaaaaa]

Description

I have modified the fuzzing workflow to handle PR from forks. Fuzzing will only be triggered on PR created by verified contributors to prevent potential security risks.
ALL WILL BE FUZZED mwahaha

This change also fix the following annoying issues:

• Reporting bugs already caught by CI: Fuzzing will now be delayed and only run if all CI checks have passed. This is implemented outside of the workflow, the PR will not be blocked.
• Reporting non-bugs in Rust: Added pattern matching to ignore error that comes from not yet implemented features in Dafny-to-Rust. (sorry Mikael!)

How has this been tested?

Tested on my own dummy repo

By submitting this pull request, I confirm that my contribution is made under the terms of the MIT license.

[stefan-aws]

LGTM