Improve our CockroachDB license management docs

[johnrk-zz]

Exalate commented:

Our current guidance on how to renew an enterprise license covers how you're production setup is unaffected, how the enterprise features stop working, a link to contact sales to renew, and a link to set a license.

But, a customer has raised the gap of our needing clarity on:

• how to monitor licenses

• are they version agnostic?

• "are no scenarios in which CRDB needs to or would call-home for licence validation/enforcement?"

• Is there a grace period? and when would restrictions be enfored.

• We could be explicit of all the enterprise features that become disabled.

Jira Issue: DOC-636

[piyush-singh]

Related: #8017

[exalate-issue-sync[bot]]

linville (mdlinville) commented: Piyush Singh Do you know if engineering or support have any recommendations for this that I could turn into docs? I don’t know the answers to the questions in the Jira description.