Allow text input for TimeStamp fields in Keystone UI

[BradNut]

At the moment tagging a schema with type of timestamp() creates a UI field which only allows entry via a calendar.
If you need to input a calendar date that is far in the past, let's say a person's birthday, you need to click all the way back on the calendar to get to that date.

This is time consuming if there are a lot of entries that need to be created whose timestamp is greater than a few months.

My current dependencies I am using are the following, so if newer packages contain this feature let me know:

    "@keystone-next/admin-ui": "^8.0.1",
    "@keystone-next/auth": "^14.0.0",
    "@keystone-next/cloudinary": "^2.0.9",
    "@keystone-next/fields": "^4.1.1",
    "@keystone-next/keystone": "^9.3.0",
    "@keystone-next/types": "^12.0.0",

[bladey]

Hey @BradNut, you're right, we only have timestamp right now, we'll be improving this going forward, thanks for calling it out.