Update gRPC client used in SDK

[WhitWaldo]

Describe the feature

Per the blog post here the gRPC library used in the SDK has been deprecated in favor of a modern version that is fully C#-based instead of an interop wrapper around a C library. The transition to this new SDK should be performed as part of the v1.16 release.

The various options are available in this GitHub repo and I'm tentatively thinking we should opt to use Grpc.Net.ClientFactory as the various client builders use IHttpClientFactory under the hood as of the v1.15 release.

Release Note

RELEASE NOTE: UPDATE Update gRPC dependency used in all Dapr clients

[WhitWaldo]

It looks like this migration may have already happened as I already see that the various packages are updated across the board. Confusingly, they retained the same Grpc.Core namespace, which is what threw me off here. It's worth poking around to see if there's any remaining work that can be done to improve gRPC connections, but this may be already taken as far as it should.

[jev-e]

As I brought this up and we have spoken about this before I am happy to complete this investigation (if it is not already underway), and get a resolution on any work that needs doing.

[WhitWaldo]

@jev-e Sure, if you see anything that needs doing, have at it, but no rush as I'll wait until after the 1.15 release to merge it.

[jev-e]

/assign