Retry: grpc maxretry attempts is hardcoded

[Leomax004]

Grpc Max Retry attempt is hardcoded and not allowing to retry more than 5

if rp.MaxAttempts > 5 {
// TODO(retry): Make the max maxAttempts configurable.
rp.MaxAttempts = 5
}

[dfawley]

Reference from gRFC:

https://github.com/grpc/proposal/blob/master/A6-client-retries.md#limits-on-retries-and-hedges

We never implemented this particular "channel arg" in Go.

[gnvk]

How is this a feature and not a bug? This makes the whole retry config pretty much unusable. And it's not even mentioned in the documentation!

[arvindbr8]

Feel free to send us a PR if you need this. I would consider missing features not bugs :)