Update grpc.md (#43138)

Remove unnecessary comma

Author: alexravenna

docs/architecture/cloud-native/grpc.md

@@ -78,7 +78,7 @@ Favor gRPC for the following scenarios:
 - Point-to-point real-time communication - gRPC can push messages in real time without polling and has excellent support for bi-directional streaming.
 - Network constrained environments – binary gRPC messages are always smaller than an equivalent text-based JSON message.
 
-At the time, of this writing, gRPC is primarily used with backend services. Modern browsers can't provide the level of HTTP/2 control required to support a front-end gRPC client. That said, there's support for [gRPC-Web with .NET](https://devblogs.microsoft.com/aspnet/grpc-web-for-net-now-available/) that enables gRPC communication from browser-based apps built with JavaScript or Blazor WebAssembly technologies. [gRPC-Web](https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-WEB.md) enables an ASP.NET Core gRPC app to support gRPC features in browser apps:
+At the time of this writing, gRPC is primarily used with backend services. Modern browsers can't provide the level of HTTP/2 control required to support a front-end gRPC client. That said, there's support for [gRPC-Web with .NET](https://devblogs.microsoft.com/aspnet/grpc-web-for-net-now-available/) that enables gRPC communication from browser-based apps built with JavaScript or Blazor WebAssembly technologies. [gRPC-Web](https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-WEB.md) enables an ASP.NET Core gRPC app to support gRPC features in browser apps:
 
 - Strongly typed, code-generated clients
 - Compact Protobuf messages