Remove the non-existed dependent repositories

Author: fenxu

.openpublishing.publish.config.json

@@ -374,12 +374,6 @@
       "branch": "master",
       "branch_mapping": {}
     },
-    {
-      "path_to_root": "media-services-v3-dotnet-quickstarts",
-      "url": "https://github.com/Azure-Samples/media-services-v3-dotnet-quickstarts",
-      "branch": "master",
-      "branch_mapping": {}
-    },
     {
       "path_to_root": "media-services-v3-dotnet-tutorials",
       "url": "https://github.com/Azure-Samples/media-services-v3-dotnet-tutorials",