Update default language to English (#309)

### What problem does this PR solve?

Update default language to English

### Type of change

- [x] Refactoring

Signed-off-by: Jin Hai <haijin.chn@gmail.com>

web/src/pages/chat/chat-configuration-modal/assistant-setting.tsx

@@ -57,7 +57,7 @@ const AssistantSetting = ({ show }: ISegmentedContentProps) => {
       <Form.Item
         name={'language'}
         label={t('language')}
-        initialValue={'Chinese'}
+        initialValue={'English'}
         tooltip="coming soon"
         style={{ display: 'none' }}
       >