Adds support for gRPC aio server that allows for async handlers #829
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Description
Added
dapr.ext.grpc.aiowhich exports anAppthat uses a grpc.aio server and allows for async handlers (for methods, topics, bindings and jobs).Also added tests and a quick example for async method invocation.
Issue reference
Please reference the issue this PR will close: #695
Checklist
Please make sure you've completed the relevant tasks for this PR, out of the following list: