Format file format from Windows/dos to Unix (#1949)

### What problem does this PR solve?

Related source file is in Windows/DOS format, they are format to Unix
format.

### Type of change

- [x] Refactoring

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

web/reducer.js

@@ -1,27 +1,26 @@
-import React, { useReducer } from 'react'
-const CHANGE_LOCALE = 'CHANGE_LOCALE'
-
-const mainContext = React.createContext()
-
-const reducer = (state, action) => {
-    switch (action.type) {
-        case CHANGE_LOCALE:
-            return { ...state, locale: action.locale || 'zh' }
-        default:
-            return state
-    }
-}
-
-const ContextProvider = (props) => {
-    const [state, dispatch] = useReducer(reducer, {
-        locale: 'zh'
-    })
-    return (
-        <mainContext.Provider value={{ state, dispatch }}>
-            {props.children}
-        </mainContext.Provider>
-    )
-}
-
-export { reducer, mainContext, ContextProvider }
-
+import React, { useReducer } from 'react';
+const CHANGE_LOCALE = 'CHANGE_LOCALE';
+
+const mainContext = React.createContext();
+
+const reducer = (state, action) => {
+  switch (action.type) {
+    case CHANGE_LOCALE:
+      return { ...state, locale: action.locale || 'zh' };
+    default:
+      return state;
+  }
+};
+
+const ContextProvider = (props) => {
+  const [state, dispatch] = useReducer(reducer, {
+    locale: 'zh',
+  });
+  return (
+    <mainContext.Provider value={{ state, dispatch }}>
+      {props.children}
+    </mainContext.Provider>
+  );
+};
+
+export { ContextProvider, mainContext, reducer };