update docs

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

en/application-dev/napi/napi-guidelines.md

@@ -156,7 +156,7 @@ struct Index {
 // Declare the N-APIs exposed to ArkTS.
 export const add: (a: number, b: number) => number;
 export const nativeCallArkTS: (a: object) => number;
-```
+``` 
 
 ## Development Guidelines
 
@@ -181,4 +181,4 @@ The ArkCompiler protects JS object threads. Improper use may cause an applicatio
 
 ### Header File Import
 
-Import **napi/native_api.h**. Otherwise, an error indicating that the N-API cannot be found will be reported.
+Import **napi/native_api.h**. Otherwise, an error indicating that the N-API cannot be found will be reported.
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