Add language for early-access

[sagetherage]

trafficstars

Add language for early-access to security.md file for future use

What does this PR do?

What issues does this PR fix or reference?

Fixes:

Previous Behavior

Remove this section if not relevant

New Behavior

Remove this section if not relevant

Merge requirements satisfied?

[NOTICE] Bug fixes or features added to Salt require tests.

• [ ] Docs
• [ ] Changelog - https://docs.saltproject.io/en/master/topics/development/changelog.html
• [ ] Tests written/updated

Commits signed with GPG?

Yes/No

Please review Salt's Contributing Guide for best practices.

See GitHub's page on GPG signing for more information about signing commits with GPG.

[sagetherage]

I don't expect this to pass test BTW

[ScriptAutomate]

@barbaricyawps Looks like we'd want to mirror updates to https://github.com/saltstack/salt/blob/master/doc/security/index.rst unless we do something like change SECURITY.md to SECURITY.rst and run an include so that the files will always be synced (like how we include the README somewhere)

[barbaricyawps]

@ScriptAutomate , probably to do that we'd want to close this PR down and just recreate, which we can take up after the 3006 release. Let's leave this as-is for now. A fresh PR will be helpful for policy conversations anyhow.

[twangboy]

Yeah, it should be [email protected]