update zh-cn/application-dev/reference/apis/js-apis-colorSpaceManager.md.

Signed-off-by: N葛亚芳 <geyafang@huawei.com>

zh-cn/application-dev/reference/apis/js-apis-colorSpaceManager.md

@@ -166,7 +166,7 @@ getColorSpaceName(): ColorSpace
 
 ```js
 try {
-    let csType = colorSpace.getColorSpaceName();
+    colorSpace.getColorSpaceName();
 } catch (err) {
     console.log(`Fail to get colorSpace's name. Cause: ` + JSON.stringify(err));
 }
@@ -198,7 +198,7 @@ getWhitePoint(): Array\<number\>
 
 ```js
 try {
-    let wp = colorSpace.getWhitePoint();
+    colorSpace.getWhitePoint();
 } catch (err) {
     console.log(`Failed to get white point. Cause: ` + JSON.stringify(err));
 }
@@ -230,9 +230,8 @@ getGamma(): number
 
 ```js
 try {
-    let gamma = colorSpace.getGamma();
+    colorSpace.getGamma();
 } catch (err) {
     console.log(`Failed to get gamma. Cause: ` + JSON.stringify(err));
 }
-```
-
+```
\ No newline at end of file