Kani Workflow Updates

[carolynzech]

Update the kani list part of our workflow to:

• Be its own step of the workflow so it can run in parallel, which is nice because it finishes much faster than the other jobs in the Kani workflow
• Use the new markdown format. This makes the list much more readable (compare current format to markdown format).

Also remove the Test Kani workflow step, because it's expensive and duplicates verification work.

[celinval]

Since you are changing this file, can you please modify the Test Kani script job to stop verifying all the harnesses. Maybe we can pass --kani-args --only-codegen which will only compile the standard library. Thanks!

[celinval]

Per offline discussion, let's delete the Test Kani script job instead.

[zhassan-aws]

Thanks.

[feliperodri]

LGTM.

[carolynzech]

trigger merge