Remove default description of timestamp field

[wysher]

before:

---

after:

---

I find this additional info message in timestamp redundant, so I introduce way to disable it.
With createdAt it's shown only on create, but for updatedAt it's ALWAYS visible in ItemView.

I'm not sure about option name, please let me know if there's better one. :)

EDIT:
here's how it looks for updatedAt - message is always visible. In my case on sidebar.

[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

To see build info of the built libraries, click here or the icon next to each commit SHA.

Latest deployment of this branch, based on commit 06d757b:

Sandbox	Source
@keystone-6/sandbox	Configuration

[dcousens]

I understand the motivation behind this, as I don't like it either.

However, won't this be misleading if the field is manually set? Maybe if db.updatedAt is configured, the field should default to read-only too?

[dcousens]

I honestly think we should probably remove the message completely.

We shouldn't be differentiating the UI behaviour of this field for db.updatedAt, when the usual workflow for these considerations would be for the developer to add a ui.description.