Remove duplicated section on tracing in README (#294)

Signed-off-by: Breina <[email protected]>

README.md

@@ -418,14 +418,5 @@ The SDK is set up to trace all gRPC communications:
 
 The SDK accepts all environment variables as described in the [OpenTelemetry specification](https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/sdk-environment-variables.md).
 
-### Tracing
-
-The SDK is set up to trace all gRPC communications:
-* All outgoing messages bear trace metadata, allowing correlation with peers.
-* Each request/response is computed as a span.
-* If you use OpenTelemetry in your program, the gRPC span will correlate using the thread local context to the parent context.
-
-The SDK accepts all environment variables as described in the [OpenTelemetry specification](https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/sdk-environment-variables.md).
-
 
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