Presently the Otel Trace Source only supports requests using OpenTelemetry's grpc protocol (via the OTLP gRPC Exporter). We'd like to allow for OTLP/HTTP Exporter requests to be receivable by the source.

There was a concern regarding different encodings between the grpc and http protocols, so we'll need to first allow for HTTP requests then test if this is the case. The Otel Source's server is backed by Armeria and configured in OtelTraceSource.java.

We'll also need to update the otel-config.yml file in the sample app to use HTTP - see the OpenTelemetry Exporter docs for more.