Update specificationRepositoryConfiguration.json

Author: dw511214992

specificationRepositoryConfiguration.json

@@ -72,7 +72,7 @@
         },
        "azure-sdk-for-net-dataplane": {
           "mainRepository": "openapi-env-test/azure-sdk-for-net",
-          "mainBranch": "yc/dpg-readme",
+          "mainBranch": "dpg-readme",
           "configFilePath": "eng/swagger_to_sdk_config.json"
         },
         "azure-sdk-for-net": {