refactor: convert function expressions to declarations (#4926)

packages/netlify-cms-widget-datetime/src/DateTimeControl.js

@@ -7,7 +7,7 @@ import DateTime from 'react-datetime';
 import moment from 'moment';
 import { buttons } from 'netlify-cms-ui-default';
 
-const NowButton = ({ t, handleChange }) => {
+function NowButton({ t, handleChange }) {
   return (
     <div
       css={css`
@@ -33,7 +33,7 @@ const NowButton = ({ t, handleChange }) => {
       </button>
     </div>
   );
-};
+}
 
 export default class DateTimeControl extends React.Component {
   static propTypes = {

packages/netlify-cms-widget-datetime/src/DateTimePreview.js

@@ -2,9 +2,9 @@ import React from 'react';
 import PropTypes from 'prop-types';
 import { WidgetPreviewContainer } from 'netlify-cms-ui-default';
 
-const DatePreview = ({ value }) => (
-  <WidgetPreviewContainer>{value ? value.toString() : null}</WidgetPreviewContainer>
-);
+function DatePreview({ value }) {
+  return <WidgetPreviewContainer>{value ? value.toString() : null}</WidgetPreviewContainer>;
+}
 
 DatePreview.propTypes = {
   value: PropTypes.oneOfType([PropTypes.object, PropTypes.string]),

packages/netlify-cms-widget-datetime/src/index.js

@@ -2,13 +2,15 @@ import controlComponent from './DateTimeControl';
 import previewComponent from './DateTimePreview';
 import schema from './schema';
 
-const Widget = (opts = {}) => ({
-  name: 'datetime',
-  controlComponent,
-  previewComponent,
-  schema,
-  ...opts,
-});
+function Widget(opts = {}) {
+  return {
+    name: 'datetime',
+    controlComponent,
+    previewComponent,
+    schema,
+    ...opts,
+  };
+}
 
 export const NetlifyCmsWidgetDatetime = { Widget, controlComponent, previewComponent };
 export default NetlifyCmsWidgetDatetime;