Verify the gRPC calls from the wasm-shim do propagate the traceid

[alexsnaps]

No description provided.

[adam-cattermole]

Currently the trace headers are not propagated if envoy starts the trace, see the discussion here https://envoyproxy.slack.com/archives/CM2CQ4XJ5/p1707487817883799.

Related issue is here: envoyproxy/envoy#22028

[adam-cattermole]

A minor follow up - I've investigated the option of generating the traceparent header ourselves and adding this to the request in wasm-shim. If for example we add the traceparent header here https://github.com/Kuadrant/wasm-shim/blob/main/src/filter/http_context.rs#L209 through self.add_http_request_header(), it still ends up being propagated back through to authorino.