[iOS] update WeexSDK.podspec (#2990)

diff --git a/WeexSDK.podspec b/WeexSDK.podspec
index bdb1615..050e37f 100644
--- a/WeexSDK.podspec
+++ b/WeexSDK.podspec
@@ -17,7 +17,7 @@
     :type => 'Apache-2.0'
   }
   s.authors      = {
-                    dev@weex.apache.org
+                    "dev" => "dev@weex.apache.org"
                    }
   s.platform     = :ios
   s.ios.deployment_target = '9.0'
@@ -123,4 +123,4 @@
   
   s.libraries = 'c++'
 
-end
\ No newline at end of file
+end