Update uni-captcha.md

docs/uniCloud/uni-captcha.md

@@ -161,7 +161,7 @@ GitCode 仓库：[https://gitee.com/dcloud/uni-captcha](https://gitee.com/dcloud
 		},
 		methods: {
 			verifyCaptcha(){
-				const uniCaptchaCo = uniCloud.importObject("uni-captcha-co")
+				const uniCaptchaCo = uniCloud.importObject("uni-captcha-demo")
 				uniCaptchaCo.verifyCaptcha(this.formData).then(e=>{
 					uni.showToast({
 						title: e.errMsg,