Fix #3608 by removing ternary and ensuring AntD FieldTemplate wraps root in Form.Item

[nickgros]

• Ensure the root field is always wrapped in Form.Item

The original ternary expression has existed since the antd theme was added in #1561. I am not familiar enough with antd to know what, if any, undesirable effects this change could cause. I looked at most of the playground examples and did not notice any new issues.

Checklist

• I'm updating documentation
  • I've checked the rendering of the Markdown text I've added
• I'm adding or updating code
  • I've added and/or updated tests. I've run npm run test:update to update snapshots, if needed.
  • I've updated docs if needed
  • I've updated the changelog with a description of the PR
• I'm adding a new feature
  • I've updated the playground with an example use of the feature

[nickgros]

The reason the error didn't show up is because the example in #3608 had a String field as the root, and the error rendering is handled by Form.Item. Since there was no Form.Item, there was no visible error message.

[heath-freenome]

Nice fix. Have you figured out what is causing #3609?

[nickgros]

Nice fix. Have you figured out what is causing #3609?

An internal call to rc-util findDOMNode but React is undefined so node instanceof React.Component incorrectly returns undefined. Might be a bundling issue? https://github.com/react-component/util/blob/master/src/Dom/findDOMNode.ts

[heath-freenome]

Actually this fix could also eliminate the need for the label changes I made to Select (and maybe Checkboxes and Radiobutton) since the label is output as part of the item. And the bug was related to the root item not having labels. Meaning that #3594 can likely be fixed by reverting my changes to those components

[nickgros]

The extra TitleField for the SelectWidget can definitely be removed. I think the other widgets did need the new label added in your change, but I'll double-check