fix：activity_detail check fail (#192)

Co-authored-by: South Drifted <shiy2008@gmail.com>

components/Activity/ActivityEditor.tsx

@@ -55,7 +55,7 @@ export class ActivityEditor extends PureComponent<ActivityEditorProps> {
 
     const form = event.currentTarget;
 
-    if (form.checkValidity() === false) return (this.validated = true);
+    if (!form.checkValidity()) return (this.validated = true);
 
     const { name } = this.props,
       data = formToJSON<ActivityFormData>(form);
@@ -271,18 +271,19 @@ export class ActivityEditor extends PureComponent<ActivityEditorProps> {
 
         <Form.Group as={Row} className="mb-3" controlId="briefInfo">
           <Form.Label column sm={2}>
-            {t('hackathon_detail')}
+            {t('activity_detail')}
             <span className="text-danger"> *</span>
           </Form.Label>
           <Col sm={10}>
             <HTMLEditor
-              name="detail"
               defaultValue={detail}
               onChange={code => (this.detailHTML = code)}
             />
             <Form.Control
-              className="d-none"
-              isInvalid={!this.detailHTML.trim() && this.validated}
+              hidden
+              name="detail"
+              required
+              defaultValue={this.detailHTML || detail}
             />
             <Form.Control.Feedback type="invalid">
               {textJoin(t('please_enter'), t('activity_detail'))}