更新版本到 1.8.6

ChangeLog
1. 修复 iOS 推流时，音频异常的问题
2. 修复 chrome 72 版本正常推流但提示推流失败的问题

lib/index.d.ts

@@ -298,7 +298,7 @@ declare module '__urtc-sdk/resolutions' {
 }
 
 declare module '__urtc-sdk/version' {
-  export const version = "1.8.5";
+  export const version = "1.8.6";
 }
 
 declare module '__urtc-sdk/token' {

package.json

@@ -1,6 +1,6 @@
 {
   "name": "urtc-sdk",
-  "version": "1.8.5",
+  "version": "1.8.6",
   "description": "UCloud RTC javascript SDK",
   "main": "lib/index.js",
   "types": "lib/index.d.ts",