rpc.request.metadata. & rpc.response.metadata need to align better with gRPCs semantics

[mbissa]

Area(s)

area:rpc

What's the problem?

gRPC cannot currently support rpc.request.metadata. & rpc.response.metadata.. We will plan for this in the future.
And the naming convention here is also not differentiating between headers and trailers.

Describe the solution you'd like

rpc.request.metadata. & rpc.response.metadata. should be changed to rpc.request.header, rpc.response.header & rpc.response.trailers.

Tip

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