Update whats-new.adoc with fine-grained starters

Signed-off-by: Chris Bono <[email protected]>

Author: onobc

spring-grpc-docs/src/main/antora/modules/ROOT/pages/whats-new.adoc

@@ -5,27 +5,13 @@
 [[what-s-new-in-0-4-0-since-0-3-0]]
 == What's New in 0.4.0 Since 0.3.0
 
-This section covers the changes made from version 0.2.0 to version 0.3.0.
+This section covers the changes made from version 0.3.0 to version 0.4.0.
 
-=== Channel Factory
-The `GrpcChannelFactory` has a new interface and its methods now return a `Channel` (instead of a `ChannelBuilder`).
-The `createChannel()` method is overloaded with a new method that accepts a `ChannelBuilderOptions` which can be used to configure the channel before it is created.
+=== Fine-grained starter modules
+The following fine-grained Spring Boot starter modules have been added:
 
-=== Client Side Observability
-A gRPC client will generate a new span for each RPC call. The span will be automatically closed when the call is completed.
+- `spring-grpc-client-spring-boot-starter` provides Netty gRPC client
+- `spring-grpc-server-spring-boot-starter` provides Netty gRPC server
+- `spring-grpc-server-spring-boot-starter` provides Servlet gRPC server
 
-=== Security in Servlet Containers
-Spring Security works with gRPC servers running in servlet containers. You can use all your favourite Spring Security features to secure your gRPC services.
-
-[[what-s-new-in-0-3-0-since-0-2-0]]
-== What's New in 0.3.0 Since 0.2.0
-
-This section covers the changes made from version 0.2.0 to version 0.3.0.
-
-=== Client Interceptors
-You can now add xref:client.adoc#client-interceptor[Client Interceptors] to created gRPC channels.
-
-=== Breaking Changes
-
-==== GrpcChannelConfigurer renamed
-The `GrpcChannelConfigurer` has been renamed to `GrpcChannelBuilderCustomizer` to more accurately represent its purpose and be consistent with the server-side terminology.
+The current coarse-grained starter `spring-grpc-spring-boot-starter` still provides Netty gRPC server and client.