Update .travis.yml

Author: zhxnlai

.travis.yml

@@ -12,7 +12,7 @@ before_script:
 - carthage bootstrap --platform osx, ios
 script:
 - xctool -project AsyncTask.xcodeproj -scheme AsyncTaskOSXTests build test
-- pod lib lint
+- pod lib lint AsyncTask.podspec
 before_deploy:
 - carthage build --no-skip-current
 - carthage archive $FRAMEWORK_NAME