Update gRPC template to use 2.23.1 (#13791)

Author: JamesNK

eng/Versions.props

@@ -225,7 +225,7 @@
     <CastleCorePackageVersion>4.2.1</CastleCorePackageVersion>
     <FSharpCorePackageVersion>4.2.1</FSharpCorePackageVersion>
     <GoogleProtobufPackageVersion>3.8.0</GoogleProtobufPackageVersion>
-    <GrpcAspNetCorePackageVersion>0.2.23-pre1</GrpcAspNetCorePackageVersion>
+    <GrpcAspNetCorePackageVersion>2.23.1</GrpcAspNetCorePackageVersion>
     <IdentityServer4AspNetIdentityPackageVersion>3.0.0</IdentityServer4AspNetIdentityPackageVersion>
     <IdentityServer4EntityFrameworkPackageVersion>3.0.0</IdentityServer4EntityFrameworkPackageVersion>
     <IdentityServer4PackageVersion>3.0.0</IdentityServer4PackageVersion>