update docs

Signed-off-by: NAnnie_wang <annie.wangli@huawei.com>

en/application-dev/reference/apis/js-apis-data-rdb.md

@@ -3,8 +3,6 @@
 > ![icon-note.gif](public_sys-resources/icon-note.gif) **NOTE**<br/>
 > The initial APIs of this module are supported since API version 7. Newly added APIs will be marked with a superscript to indicate their earliest API version.
 
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 ## Modules to Import
 
 ```js