[AutoPR Microsoft.Azure.Management.ResourceGraph] revise readme.md for resourcegraph#690

openapi-sdkautomation[bot] wants to merge 1 commit intosdkAutomation/Microsoft.Azure.Management.ResourceGraphAzureSDKAutomation/azure-sdk-for-net:sdkAutomation/Microsoft.Azure.Management.ResourceGraphfrom

sdkAutomation/Microsoft.Azure.Management.ResourceGraph@8688AzureSDKAutomation/azure-sdk-for-net:sdkAutomation/Microsoft.Azure.Management.ResourceGraph@8688Copy head branch name to clipboard