updated docs against 5324

Signed-off-by: Nwusongqing <wusongqing@huawei.com>

en/application-dev/reference/apis/js-apis-medialibrary.md

 # Media Library Management
 
-> **NOTE**<br>
+> **NOTE**
+>
 > This component is supported since API version 6. Updates will be marked with a superscript to indicate their earliest API version.
 
 ## Modules to Import
@@ -93,7 +94,7 @@ let imagesfetchOp = {
     selections: fileKeyObj.MEDIA_TYPE + '= ?',
     selectionArgs: [imageType.toString()],
 };
-mediaLibrary.getFileAssets(imagesfetchOp, (error, fetchFileResult) => {
+media.getFileAssets(imagesfetchOp, (error, fetchFileResult) => {
     if (fetchFileResult != undefined) {
         console.info('mediaLibraryTest : ASSET_CALLBACK fetchFileResult success');
         fetchFileResult.getAllObject((err, fileAssetList) => {
@@ -135,7 +136,7 @@ let imagesfetchOp = {
     selections: fileKeyObj.MEDIA_TYPE + '= ?',
     selectionArgs: [imageType.toString()],
 };
-mediaLibrary.getFileAssets(imagesfetchOp).then(function(fetchFileResult){
+media.getFileAssets(imagesfetchOp).then(function(fetchFileResult){
     console.info("getFileAssets successfully:"+ JSON.stringify(dir));
 }).catch(function(err){
     console.info("getFileAssets failed with error:"+ err);
@@ -182,7 +183,7 @@ Unsubscribes from the media library changes. This API uses an asynchronous callb
 **Example**
 
 ```
-mediaLibrary.off('imageChange', () => {
+media.off('imageChange', () => {
     // stop listening success
 })
 ```
@@ -350,7 +351,7 @@ let AlbumNoArgsfetchOp = {
     selections: '',
     selectionArgs: [],
 };
-mediaLibrary.getAlbums(AlbumNoArgsfetchOp, (err, albumList) => {
+media.getAlbums(AlbumNoArgsfetchOp, (err, albumList) => {
     if (albumList != undefined) {
         const album = albumList[0];
         console.info('album.albumName = ' + album.albumName);
@@ -390,7 +391,7 @@ let AlbumNoArgsfetchOp = {
     selections: '',
     selectionArgs: [],
 };
-mediaLibrary.getAlbums(AlbumNoArgsfetchOp).then(function(albumList){
+media.getAlbums(AlbumNoArgsfetchOp).then(function(albumList){
     console.info("getAlbums successfully:"+ JSON.stringify(albumList));
 }).catch(function(err){
     console.info("getAlbums failed with error:"+ err);
@@ -439,7 +440,6 @@ Call this API when you no longer need to use the APIs in the **MediaLibrary** in
 **Example**
 
 ```
-var media = mediaLibrary.getMediaLibrary(context);
 media.release()
 ```