Update CONTRIBUTING.md: CLA -> DCO (#178)

Close ClientStreaming on context cancellation (#152)

On `CloseResponse` we must have stopped the connection and it is now
safe to close the span. To handle context cancellation and ensure the
span is always closed
[`context.AfterFunc`](https://pkg.go.dev/context#AfterFunc) is added
with a simpler backport for !go1.21.

Drop actions cache for setup-go (#137)

Clean up README code sample

Make option to omit trace events apply to streaming RPCs (#123)

- Changes name of option from `OmitRPCEvents` to `OmitTraceEvents` to be
more clear
- Omits trace events for streaming too
- Adds tests
Closes: #92

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Co-authored-by: Akshay Shah <[email protected]>

Update to semconv/v1.20.0 (#113)

Upgrades from `v1.19.0` to `v1.20.0`

Update go deps to otel v1.15.1/v0.38.1 (#106)

- Updates deps
- Fixes test cases

Fix license years (#88)

Changes from `2023` to `2022-2023`