Integration with oss-fuzz fuzzing service

Hi @m4b, I would like to help integrate this project into [OSS-Fuzz](https://github.com/google/oss-fuzz).

- As an initial step for integration I have created this PR: https://github.com/google/oss-fuzz/pull/8646, it contains necessary logic from an OSS-Fuzz perspective to integrate goblin.

- OSS-Fuzz is a free service run by Google that performs continuous fuzzing of important open source projects.

- As goblin already have cargo-fuzz based fuzzing implemented, this makes it easily compatible with oss-fuzz out of box.

- If you would like to integrate, the only thing I need is a list of email(s), it must be associated with a google account like
gmail ([why?](https://google.github.io/oss-fuzz/faq/#why-do-you-require-a-google-account-for-authentication)). by doing that, the provided email(s) will get access to the data produced by OSS-Fuzz, such as bug reports, coverage reports and more stats.

~~- As an alternative, if you don't have a google/gmail id, but still wish to integrate. I can add my mail id for time being and monitor bug/crashes.~~

- Notice the email(s) affiliated with the project will be public in the OSS-Fuzz repo, as they will be part of a configuration file.

Start by reviewing the referenced OSS-Fuzz pull request 8646 and goblin's existing cargo-fuzz setup. The integration is complete from the OSS-Fuzz side when the project is accepted and maintainers provide the public Google-associated email address or addresses required for access.

Written by the indexing model from the issue text.