avoid duplicate package [skip ci]

appveyor.yml

@@ -29,7 +29,7 @@ install:
   # make commit message env var shorter
   - SET CM=%APPVEYOR_REPO_COMMIT_MESSAGE%
   - ECHO commit message %CM%
-  - if not "%CM%" == "%CM:[publish binary]=%" node-pre-gyp --msvs_version=2013 package publish 2>&1
+  - if not "%CM%" == "%CM:[publish binary]=%" node-pre-gyp --msvs_version=2013 publish 2>&1
 
 artifacts:
   - path: build\stage