fix：修复host签名时不兼容全球加速域名

Author: livehigh

package.json

@@ -1,6 +1,6 @@
 {
   "name": "cos-nodejs-sdk-v5",
-  "version": "2.11.5",
+  "version": "2.11.6",
   "description": "cos nodejs sdk v5",
   "main": "index.js",
   "types": "index.d.ts",

sdk/base.js

@@ -3321,7 +3321,7 @@ var getSignHost = function (opt) {
         protocol: this.options.Protocol,
         domain: this.options.Domain,
         bucket: opt.Bucket,
-        region: opt.Region,
+        region: this.options.UseAccelerate ? 'accelerate' : opt.Region,
     });
     var urlHost = url.replace(/^https?:\/\/([^/]+)(\/.*)?$/, '$1');
     var standardHostReg = new RegExp('^([a-z\\d-]+-\\d+\\.)?(cos|cosv6|ci|pic)\\.([a-z\\d-]+)\\.myqcloud\\.com$');