Security policy is needed

[zefr0x]

As this project is getting more popular and used in more critical infrastructure, there should be a clear and easy way to report security issues and an effective way to notify any project relaying on sea-orm of potential threats.

I suggest opening the private security advisories in Github (from the Security tab) for this repo or even from the whole SeaQl organisation.

Also it would be great to provide a SECURITY.md file for details about the process and the scope. (something like this)

[tyt2y3]

Thank you for your suggestions, you have provided a great template!
We're still working out the right approach here, but we will get to it soon.