Avoid deprecated nameResolverFactory

[laglangyue]

I was reading the code for name solver and found a todo item, hoping to resolve it.

motivation

same issue in akka-grpc akka/akka-grpc#1092

code in pekko org.apache.pekko.grpc.internal.NettyClientUtils

pekko-grpc/runtime/src/main/scala/org/apache/pekko/grpc/internal/NettyClientUtils.scala

Lines 49 to 64 in 7f4b94c

	@nowarn("cat=deprecation")
	var builder =
	NettyChannelBuilder
	// Not sure why netty wants to be able to shoe-horn the target into a URI... but ok,
	// we follow their lead and encode the service name as the 'authority' of the URI.
	.forTarget("//" + settings.serviceName)
	.flowControlWindow(NettyChannelBuilder.DEFAULT_FLOW_CONTROL_WINDOW)
	// TODO avoid nameResolverFactory #1092, then 'nowarn' can be removed above
	.nameResolverFactory(
	new PekkoDiscoveryNameResolverProvider(
	settings.serviceDiscovery,
	settings.defaultPort,
	settings.serviceName,
	settings.servicePortName,
	settings.serviceProtocol,
	settings.resolveTimeout))

changes

according to grpc-java

https://github.com/grpc/grpc-java/blob/497e1552172632107574d67d7c092a3f5a39a980/examples/src/main/java/io/grpc/examples/nameresolve/NameResolveClient.java#L39

we just need

NameResolverRegistry.getDefaultRegistry.register(
      new PekkoDiscoveryNameResolverProvider(
        settings.serviceDiscovery,
        settings.defaultPort,
        settings.serviceName,
        settings.servicePortName,
        settings.serviceProtocol,
        settings.resolveTimeout))

[laglangyue]

@raboof
Akka's issue was created by you. Do you have any ideas?
Should we add a PekkoNameResolverRegister to wrapper the NameResolverRegistry in grpc-java?