Title: Support for sending OpenTelemetry Tracing over HTTP/Protobuf endpoint

Description:

Today, Envoy support OpenTelemetry based tracing but only over a gRPC endpoint. Are there any plan to support for HTTP/Protobuf endpoint?

My use-case: I'm using Fluent Bit to log Envoy's access logs to my telemetry store but when it comes to OTel, Fluent Bit only supports listening to OTLP events over HTTP/Protobuf endpoint and not gRPC. Hence wondering are there any plans to add support for sending OTel traces over a HTTP/Protobuf endpoint along with gRPC endpoint?

[optional Relevant Links:]

Any extra documentation required to understand the issue.
https://docs.fluentbit.io/manual/pipeline/inputs/opentelemetry