修复storage示例代码错误

Signed-off-by: Nli_juntao <lijuntao9@huawei.com>

zh-cn/application-dev/reference/apis/js-apis-data-storage.md

@@ -46,7 +46,7 @@ getStorageSync(path: string): Storage
   ```js
   import data_storage from '@ohos.data.storage'
   
-  var path = '/data/storage/el2/database/test_storage'
+  let path = '/data/storage/el2/database'
   let storage = data_storage.getStorageSync(path + '/mystore')
   storage.putSync('startup', 'auto')
   storage.flushSync()
@@ -72,7 +72,7 @@ getStorage(path: string, callback: AsyncCallback<Storage>): void
   ```js
   import data_storage from '@ohos.data.storage'
   
-  var path = '/data/storage/el2/database/test_storage'
+  let path = '/data/storage/el2/database'
   data_storage.getStorage(path + '/mystore', function (err, storage) {
       if (err) {
           console.info("Get the storage failed, path: " + path + '/mystore')
@@ -106,7 +106,7 @@ getStorage(path: string): Promise<Storage>
   ```js
   import data_storage from '@ohos.data.storage'
   
-  var path = '/data/storage/el2/database/test_storage'
+  let path = '/data/storage/el2/database'
   
   let getPromise = data_storage.getStorage(path + '/mystore')
   getPromise.then((storage) => {
@@ -133,6 +133,7 @@ deleteStorageSync(path: string): void
 
 **示例：**
   ```js
+  let path = '/data/storage/el2/database'
   data_storage.deleteStorageSync(path + '/mystore')
   ```
 
@@ -153,6 +154,7 @@ deleteStorage(path: string, callback: AsyncCallback<void>): void
 
 **示例：**
   ```js
+  let path = '/data/storage/el2/database'
   data_storage.deleteStorage(path + '/mystore', function (err) {
       if (err) {
           console.info("Deleted failed with err: " + err)
@@ -183,6 +185,7 @@ deleteStorage(path: string): Promise<void>
 
 **示例：**
   ```js
+  let path = '/data/storage/el2/database'
   let promisedelSt = data_storage.deleteStorage(path + '/mystore')
   promisedelSt.then(() => {
       console.info("Deleted successfully.")
@@ -207,6 +210,7 @@ removeStorageFromCacheSync(path: string): void
 
 **示例：**
   ```js
+  let path = '/data/storage/el2/database'
   data_storage.removeStorageFromCacheSync(path + '/mystore')
   ```
 
@@ -227,6 +231,7 @@ removeStorageFromCache(path: string, callback: AsyncCallback<void>): void
 
 **示例：**
   ```js
+  let path = '/data/storage/el2/database'
   data_storage.removeStorageFromCache(path + '/mystore', function (err) {
       if (err) {
           console.info("Removed storage from cache failed with err: " + err)
@@ -257,6 +262,7 @@ removeStorageFromCache(path: string): Promise<void>
 
 **示例：**
   ```js
+  let path = '/data/storage/el2/database'
   let promiserevSt = data_storage.removeStorageFromCache(path + '/mystore')
   promiserevSt.then(() => {
       console.info("Removed storage from cache successfully.")