[Microsoft.StorageSync] Update .NET SDK to 7.0.0 to address swagger correctness changes (Azure#27271)

* generate updated SDK for v7

* Fix SdkInfo file

* Update tests

Author: anpint

eng/mgmt/mgmtmetadata/storagesync_resource-manager.txt

@@ -3,12 +3,17 @@ AutoRest installed successfully.
 Commencing code generation
 Generating CSharp code
 Executing AutoRest command
-cmd.exe /c autorest.cmd https://github.com/Azure/azure-rest-api-specs/blob/master/specification/storagesync/resource-manager/readme.md --csharp --version=v2 --reflect-api-versions --csharp-sdks-folder=D:\github\anpint\azure-sdk-for-net\sdk
-2021-06-11 18:17:24 UTC
+cmd.exe /c autorest.cmd https://github.com/Azure/azure-rest-api-specs/blob/main/specification/storagesync/resource-manager/readme.md --csharp --version=2.0.4421 --reflect-api-versions --csharp-sdks-folder=D:\github\anpint\azure-sdk-for-net\sdk
+2022-03-01 18:54:17 UTC
 Azure-rest-api-specs repository information
 GitHub fork: Azure
-Branch:      master
-Commit:      e92d236d96ab4e229a9943ddea7a7534982a4028
+Branch:      main
+Commit:      56cf5d41fd670c6c13a13ba761fb93a26b374c59
 AutoRest information
-Requested version: v2
+Requested version: 2.0.4421
 Bootstrapper version:    [email protected]
+npm notice 
+npm notice New minor version of npm available! 8.3.0 -> 8.5.2
+npm notice Changelog: <https://github.com/npm/cli/releases/tag/v8.5.2>
+npm notice Run `npm install -g [email protected]` to update!
+npm notice