Set package.json preview field to true

Author: laggage

package.json

@@ -4,7 +4,7 @@
     "description": "A vscode extension used to write and publish blog post to cnblogs",
     "version": "0.0.1",
     "license": "LICENSE.txt",
-    "preview": true,
+    "preview": false,
     "publisher": "cnblogs",
     "repository": {
         "type": "github",